Method of sorting and/or processing waste material and processed material produced thereby

ABSTRACT

A method of sorting waste material is disclosed herein, the method comprising separating materials in the waste material according to specific gravity, by contacting the waste material with a liquid selected such that a portion of the waste material sinks, to thereby obtain a sorted material containing at least 90 weight percents of material having a specific gravity within a pre-selected range. Further disclosed herein is a method of processing waste material by separating materials in the waste material according to specific gravity as described herein to remove at least a portion of inorganic materials in the waste material, and subjecting a feedstock comprising the obtained sorted material to mixing via shear forces and to heating. Further disclose herein are a polymeric material obtainable by the method of processing waste material, articles-of-manufacturing comprising same, and systems for sorting and processing waste material.

FIELD AND BACKGROUND OF THE INVENTION

The present invention, in some embodiments thereof, relates to wastetreatment and, more particularly, but not exclusively, to methods andsystems for sorting and/or processing waste material and processedmaterial produced thereby.

The most common method of disposing of waste material is deposition inlandfills. However, environmental concerns and/or the cost of land mayrender this method unsatisfactory.

Standard recycling of waste material typically requires sorting of wastematerial into different types of material, and recycling or discardingthe different types of material separately.

An alternative to standard recycling is production of refuse-derivedfuel (RDF) by shredding and dehydrating solid waste material, andcombustion of the RDF in power plants.

U.S. Pat. No. 6,017,475 describes a process of converting householdgarbage into useful byproducts by reducing the garbage to an aggregateshard, optionally expelling liquid from the aggregate shard, and heatingthe aggregate shard under pressure to create a pulp. A system comprisinga grinder for converting household garbage to an aggregate shard, and ahydrolyzer for decomposing the remaining aggregate shard after theliquid has been removed, to form the pulp, is also described. Theprocess hydrolyzes lignocellulose in the garbage, to obtain an aggregatecellulose pulp having traces of metals and plastics. As furtherdescribed therein, the aggregate cellulose pulp can be separated intopure cellulose pulp and a residue containing inorganic materials.

U.S. Pat. No. 7,497,335 describes “hydrogravity” separation of amultiple domain solid feedstock to produce particles of eachsubstantially a single domain, each type of particle having a differentdensity. Particles are slurried into a suitable fluid to effect binaryseparation of the mixture of particles into a stream with a higheraverage specific gravity and a stream with a lower average specificgravity.

International Patent Application having Publication No. WO 2006/035441describes a method of encapsulating pieces of waste with melted plasticby heating and mixing.

International Patent Application having Publication No. WO 2010/082202describes a composite material prepared by drying waste, and heating thedried waste while mixing under shear forces. The composite material hasthermoplastic properties, and is processed to obtain useful articles.

Additional background art includes International Patent Applicationshaving Publication Nos. WO 2005/077630, WO 2005/092708 and WO2006/079842; European Patent No. 1711323; KR 2003/0014929; U.S. Pat.Nos. 3,850,771, 4,013,616, 4,772,430, 4,968,463, 5,217,655, 6,017,475,6,253,527 and 6,423,254; and U.S. patent applications having PublicationNos. 2004/0080072 and 2004/0080072.

SUMMARY OF THE INVENTION

According to an aspect of some embodiments of the invention, there isprovided a method of processing waste material so as to form anon-particulate processed material.

According to some embodiments, the method comprises:

removing at least a portion of inorganic materials in the wastematerial, to thereby obtain a sorted material containing at least 90weight percents of an organic material;

providing a feedstock having a water content of at least 15 weightpercents, wherein at least 50 weight percents of the dry weight of thefeedstock is the sorted material;

subjecting the feedstock to mixing via shear forces; and

subjecting the feedstock to heating, thereby obtaining a non-particulateprocessed material.

According to some embodiments, the removing comprises separatingmaterials according to specific gravity, the separating comprisingcontacting the waste material with a liquid selected such that at leasta portion of inorganic materials sink; and the feedstock is subjected tothe mixing and the heating without being dried.

According to an aspect of some embodiments of the invention, there isprovided a method of sorting waste material, the method comprising:

separating materials in the waste material according to specificgravity, the separating comprising contacting the waste material with anaqueous liquid selected such that a portion of the waste material sinks,to thereby obtain a sorted material containing at least 90 weightpercents of material having a specific gravity within a pre-selectedrange.

According to an aspect of some embodiments of the invention, there isprovided a polymeric material obtainable by a method of processing wastematerial described herein.

According to an aspect of some embodiments of the invention, there isprovided an article-of-manufacturing formed from the polymeric materialdescribed herein.

According to an aspect of some embodiments of the invention, there isprovided a use of a waste material for the production of thearticle-of-manufacturing described herein.

According to an aspect of some embodiments of the invention, there isprovided a system for processing a waste material to form anon-particulate processed material.

According to some embodiments, the system comprises:

a separator configured for removing at least a portion of inorganicmaterials from the waste material by separating materials in the wastematerial according to specific gravity, the separator containing aliquid selected such that at least a portion of inorganic materialssink, to thereby provide a sorted material containing at least 90 weightpercents of an organic material;

an apparatus for subjecting a feedstock to mixing via shear forces, theapparatus comprising a first mixing zone and a second mixing zone, eachindependently being adapted for subjecting the waste material toheating; and

a first vent and a second vent, each being adapted for removing gasesreleased during the mixing and the heating from the apparatus,

the system being configured for providing to the apparatus a feedstockcomprising the sorted material, and having a water content of at least15 weight percents, and

the apparatus being configured for subjecting the feedstock to mixing inthe first mixing zone and removing gases from the first vent, andsubsequently subjecting the feedstock to mixing in the second mixingzone and removing gases from the second vent, to thereby obtain aprocessed material, wherein the feedstock is subjected to the mixing andthe heating without being dried.

According to an aspect of some embodiments of the invention, there isprovided a system for sorting a waste material.

According to some embodiments, the system comprises:

a separator configured for separating materials in the waste materialaccording to specific gravity, the separator containing a liquidselected such that a portion of the waste material sinks, to therebyobtain a sorted material containing at least 90 weight percents ofmaterial having a specific gravity within a pre-selected range.

According to some embodiments of the invention, at least 90 weightpercents of the dry weight of the feedstock is the sorted material.

According to some embodiments of the invention, at least 99 weightpercents of the dry weight of the feedstock is the sorted material.

According to some embodiments of the invention, less than 10% of avolume of the non-particulate processed material consists of particleshaving a volume of at least 0.2 mm³.

According to some embodiments of the invention, separating materialsaccording to specific gravity comprises obtaining a sorted materialcontaining at least 90 weight percents of material having a specificgravity within a pre-selected range.

According to some embodiments of the invention, separating materialsaccording to specific gravity further comprises removing at least aportion of a polymer selected from the group consisting of a thermosetpolymer and a synthetic polymer having a melting point of at least 250°C. in the waste material, to thereby obtain a sorted material containingat least 90 weight percents of an organic material other than thethermoset polymer and the synthetic polymer having a melting point of atleast 250° C.

According to some embodiments of the invention, the water content of thefeedstock is at least 40 weight percents.

According to some embodiments of the invention, the water content of thefeedstock ranges from 50 to 70 weight percents.

According to some embodiments of the invention, at least 70 weightpercents of the dry weight of the feedstock is lignocellulose.

According to some embodiments of the invention, no more than 95 weightpercents of the dry weight of the feedstock is lignocellulose.

According to some embodiments of the invention, no more than 5 weightpercents of the dry weight of the feedstock is inorganic material.

According to some embodiments of the invention, from 15 to 30 weightpercents of the dry weight of the feedstock comprises syntheticpolymers.

According to some embodiments of the invention, at least 50 weightpercents of synthetic polymers in the feedstock is polyolefins.

According to some embodiments of the invention, at least 1 weight of thedry weight of the feedstock is inorganic salts.

According to some embodiments of the invention, the mixing and theheating are performed until a water content of the processed material isless than 1 weight percent.

According to some embodiments of the invention, the method furthercomprises contacting the waste material or sorted material with anacidic substance, to thereby provide the feedstock.

According to some embodiments of the invention, the acidic substancecomprises hydrochloric acid.

According to some embodiments of the invention, the acidic substancecomprises an aqueous solution characterized by a pH of less than 4.

According to some embodiments of the invention, the method furthercomprises mixing the sorted material with an additional material, tothereby provide the feedstock.

According to some embodiments of the invention, the additional materialcomprises at least one carbohydrate.

According to some embodiments of the invention, the processed materialcomprises a polymeric material.

According to some embodiments of the invention, a concentration ofcarbon in the processed material is at least 55 weight percents.

According to some embodiments of the invention, a concentration ofoxygen in the processed material is at least 20 weight percents.

According to some embodiments of the invention, a total concentration ofcarbon and oxygen in the processed material is at least 80 weightpercents.

According to some embodiments of the invention, a total concentration ofcarbon, hydrogen and oxygen in the processed material is at least 90weight percents.

According to some embodiments of the invention, a total concentration ofcarbon, hydrogen, oxygen, nitrogen, alkali metal and halogen atoms inthe processed material is at least 93 weight percents.

According to some embodiments of the invention, at least 95 percent ofthe non-hydrogen atoms in the processed material are carbon or oxygenatoms.

According to some embodiments of the invention, at least 97 percent ofthe non-hydrogen atoms in the processed material are carbon, oxygen,nitrogen, alkali metal or halogen atoms.

According to some embodiments of the invention, a molar concentration ofalkali metals in the processed material is at least 50% higher than amolar concentration of alkali metals in the dry weight of the wastematerial.

According to some embodiments of the invention, a molar concentration ofhalogens in the processed material is at least 50% higher than a molarconcentration of halogens in the dry weight of the waste material.

According to some embodiments of the invention, the waste material is ashredded waste material.

According to some embodiments of the invention, the method furthercomprises shredding the waste material prior to contacting the wastematerial with the liquid.

According to some embodiments of the invention, the method furthercomprises shredding the sorted material subsequent to contacting thewaste material with the liquid.

According to some embodiments of the invention, the method comprisescontacting the waste material with an aqueous liquid, to thereby obtaina partially sorted material, and further comprises subjecting thepartially sorted material to at least one additional cycle of separatingmaterials according to specific gravity, the separating comprisingcontacting the partially sorted material with an additional liquid, tothereby obtain the sorted material.

According to some embodiments of the invention, the method furthercomprises shredding the sorted material subsequent to contacting thepartially sorted material with the additional liquid.

According to some embodiments of the invention, at least one of the atleast one additional cycle of separating materials according to specificgravity comprises removing material which sinks in the additionalliquid.

According to some embodiments of the invention, at least one of the atleast one additional cycle of separating materials according to specificgravity comprises removing material which floats in the additionalliquid.

According to some embodiments of the invention, the method furthercomprises separating at least a portion of oils from the sortedmaterial.

According to some embodiments of the invention, the polymeric materialdescribed herein is a thermoplastic polymeric material.

According to some embodiments of the invention, the polymeric materialdescribed herein is characterized by a density below 1.2 gram/cm³.

According to some embodiments of the invention, a concentration ofcarbon in the polymeric material is at least 55 weight percents.

According to some embodiments of the invention, a concentration ofoxygen in the polymeric material is at least 20 weight percents.

According to some embodiments of the invention, a total concentration ofcarbon and oxygen in the polymeric material is at least 80 weightpercents.

According to some embodiments of the invention, a total concentration ofcarbon, hydrogen and oxygen in the polymeric material is at least 90weight percents.

According to some embodiments of the invention, a total concentration ofcarbon, hydrogen, oxygen, nitrogen, alkali metal and halogen atoms inthe polymeric material is at least 93 weight percents.

According to some embodiments of the invention, at least 95 percent ofthe non-hydrogen atoms in the polymeric material are carbon or oxygenatoms.

According to some embodiments of the invention, at least 97 percent ofthe non-hydrogen atoms in the polymeric material are carbon, oxygen,nitrogen, alkali metal or halogen atoms.

According to some embodiments of the invention, a molar concentration ofalkali metals in the polymeric material is at least 50% higher than amolar concentration of alkali metals in the dry weight of the wastematerial.

According to some embodiments of the invention, a molar concentration ofhalogens in the polymeric material is at least 50% higher than a molarconcentration of halogens in the dry weight of the waste material.

According to some embodiments of the invention, a melt-flow index of thepolymeric material is at least 1 gram per 10 minutes at a temperature of190° C.

According to some embodiments of the invention, thearticle-of-manufacturing comprises two or more materials adhered toand/or blended with one another, wherein at least one of the materialsis the polymeric material described herein.

According to some embodiments of the invention, at least one of the twoor more materials in the article-of-manufacturing is a plastic.

According to some embodiments of the invention, the system comprises atleast one separator configured for separating materials in the wastematerial according to specific gravity, the at least one separator beingconfigured for obtaining a sorted material containing at least 90 weightpercents of a material having a specific gravity within a pre-selectedrange.

According to some embodiments of the invention, the system is configuredfor removing at least a portion of a polymer selected from the groupconsisting of a thermoset polymer and a synthetic polymer having amelting point of at least 250° C. from the waste material, to therebyobtain a sorted material containing at least 90 weight percents of anorganic material other than the thermoset polymer and the syntheticpolymer having a melting point of at least 250° C.

According to some embodiments of the invention, the first mixing zoneand the second mixing zone are each independently adapted for heatingthe feedstock at a temperature in a range of from 90° C. to 230° C.

According to some embodiments of the invention, the system furthercomprises a sensor for determining a water content of material in theapparatus described herein.

According to some embodiments of the invention, the apparatus comprisesa screw for effecting the mixing.

According to some embodiments of the invention, the system is configuredfor contacting the waste material or sorted material with an acidicsubstance.

According to some embodiments of the invention, the system is configuredfor mixing the sorted material and/or the processed material with anadditional material.

According to some embodiments of the invention, the system furthercomprises a shredder configured for shredding the waste material priorto contacting the waste material with the liquid.

According to some embodiments of the invention, the system furthercomprises a shredder configured for shredding the sorted materialsubsequent to contacting the waste material with the liquid.

According to some embodiments of the invention, the system furthercomprises a monitor for monitoring a specific gravity of the liquid inthe separator, wherein the system is configured to adjust a specificgravity of the liquid in the separator to a predetermined value.

According to some embodiments of the invention, the system comprises afirst separator configured for separating materials according tospecific gravity to thereby obtain a partially sorted material, and atleast one additional separator configured for subjecting the partiallysorted material to at least one additional cycle of separating materialsaccording to specific gravity, the additional separator containing anadditional liquid selected such that a portion of the partially sortedmaterial sinks.

According to some embodiments of the invention, the system furthercomprises a shredder configured for shredding the sorted materialsubsequent to contacting the partially sorted material with theadditional liquid in the additional separator.

According to some embodiments of the invention, a specific gravity ofthe liquid is at least 1.05.

According to some embodiments of the invention, the liquid comprises anaqueous salt solution.

According to some embodiments of the invention, the salt is sodiumchloride.

According to some embodiments of the invention, a concentration of thesalt in the aqueous salt solution is at least 10 weight percents.

According to some embodiments of the invention, a water content of theprocessed material is less than 1 weight percent.

According to some embodiments of the invention, the pre-selected rangeis no more than 1.25.

According to some embodiments of the invention, the system furthercomprises at least one apparatus configured for separating oils fromsaid liquid.

Embodiments of the present invention encompass any combination of any ofthe embodiments described herein, unless otherwise indicated.

Unless otherwise defined, all technical and/or scientific terms usedherein have the same meaning as commonly understood by one of ordinaryskill in the art to which the invention pertains. Although methods andmaterials similar or equivalent to those described herein can be used inthe practice or testing of embodiments of the invention, exemplarymethods and/or materials are described below. In case of conflict, thepatent specification, including definitions, will control. In addition,the materials, methods, and examples are illustrative only and are notintended to be necessarily limiting.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Some embodiments of the invention are herein described, by way ofexample only, with reference to the accompanying drawings. With specificreference now to the drawings in detail, it is stressed that theparticulars shown are by way of example and for purposes of illustrativediscussion of embodiments of the invention. In this regard, thedescription taken with the drawings makes apparent to those skilled inthe art how embodiments of the invention may be practiced.

In the drawings:

FIG. 1 is a flow chart depicting a method of separating waste materialaccording to some embodiments of the invention;

FIG. 2 is a flow chart depicting a method of processing sorted wastematerial according to some embodiments of the invention;

FIG. 3 is a scheme depicting a system for separating and processingwaste material according to some embodiments of the invention;

FIG. 4 is a scheme depicting a system for processing waste materialaccording to some embodiments of the invention (large arrow showsdirection of waste material; small arrows show direction of releasedgases);

FIGS. 5A and 5B are images of a cylindrical sample of extruded processedmaterial according to some embodiments of the invention (side view FIG.5A; cross-section FIG. 5B; diameter of sample is approximately 10 cm);

FIG. 6 is a graph showing heat flow as a function of temperature duringa calorimetry scan (at a rate of 10° C. per minute) of a processedmaterial according to some embodiments of the invention, as well as thetemperature of observed phase transitions (represented by peaks) andheat of phase transitions;

FIG. 7 shows an infra-red spectrum of processed material prepared fromwaste material with (green) and without (blue) separation of the wastematerial according to some embodiments of the invention;

FIG. 8 is a graph presenting an electron paramagnetic resonance (EPR)spectrum of a processed material according to some embodiments of theinvention, including peaks representing g1, g2 and g3 values; locationsof a peak representing g values of 2.0 (characteristic of carbonradical) and 3.4 (characteristic of cellulose) are also shown;

FIGS. 9A and 9B present portions of an NMR spectrum (at different y-axisscales) of a processed material according to some embodiments of theinvention;

FIGS. 10A and 10B show NMR spectra of a filtrate of sea salt aqueoussolution (about 20 weight percents) (FIG. 10A) and fresh water (FIG.10B), each filtrate being obtained after 3 hours incubation with plantbiomass;

FIG. 11 is a scheme depicting a system for separating waste materialaccording to some embodiments of the invention; and

FIG. 12 is a scheme depicting a system for separating and processingwaste material according to some embodiments of the invention.

DESCRIPTION OF SPECIFIC EMBODIMENTS OF THE INVENTION

The present invention, in some embodiments thereof, relates to wastetreatment and, more particularly, but not exclusively, to methods andsystems for sorting and/or processing waste material and waste materialproduced thereby.

Before explaining at least one embodiment of the invention in detail, itis to be understood that the invention is not necessarily limited in itsapplication to the details of construction and the arrangement of thecomponents and/or methods set forth in the following description and/orillustrated in the drawings and/or the Examples. The invention iscapable of other embodiments or of being practiced or carried out invarious ways.

The present inventor has uncovered that separating materials in a wastematerial according to specific gravity can be used to obtain, in anefficient and cost-effective manner, a sorted material useful forfurther processing without drying the sorted material. The presentinventor has further uncovered that separation according to specificgravity can beneficially affect both the process progress and parametersand properties of the obtained processed material. For example,contacting waste materials (e.g., unsorted waste materials) with aliquid such as an aqueous solution can be utilized to advantageouslyseparate some materials, particularly inorganic materials, from theobtained sorted materials and/or to increase a water content to a levelparticularly suitable for processing. Furthermore, separation bycontacting waste materials with a liquid may be readily performed usingwet waste material (e.g., waste material that has not been dried),whereas wet waste material poses an obstacle to other separationtechniques, for example, by resulting in fragments of different types ofmaterial sticking to one another. The present inventor has furtherdemonstrated that the processed waste material, obtained upon specificgravity separation, exhibits exceptional and controllable properties.

Referring now to the drawings, FIG. 1 illustrates a general procedurefor separating waste material according to specific gravity, accordingto exemplary embodiments of the invention, as described in detail in theExamples section that follows.

FIG. 2 illustrates a general procedure for processing a sorted material,according to exemplary embodiments of the invention, as described indetail in the Examples section that follows.

FIG. 3 illustrates a system for separating and processing a wastematerial, according to exemplary embodiments of the invention, asdescribed in detail herein under. FIG. 4 illustrates a system forprocessing a material (e.g., a sorted material), according to exemplaryembodiments of the invention, as described in detail herein under.

FIGS. 5A and 5B show a relatively homogeneous processed materialproduced according to exemplary embodiments of the invention.

FIGS. 6-9B show physical properties of processed material producedaccording to exemplary embodiments of the invention, as described indetail in the Examples section that follows.

FIGS. 10A and 10B show that hypertonic solution facilitates release ofcarbohydrates from biomass.

FIG. 11 illustrates a system for separating waste material according tospecific gravity, according to exemplary embodiments of the invention,as described in detail herein under.

FIG. 12 illustrates a system for separating waste material according tospecific gravity and processing the obtained sorted material, accordingto exemplary embodiments of the invention, as described in detail in theExamples section that follows.

According to an aspect of some embodiments of the present invention,there is provided a method of sorting waste material, to thereby obtaina sorted material. In some embodiments, the method according to thisaspect of the present invention is effected by separating materials inthe waste material according to specific gravity. In some embodiments,separating is effected by contacting the waste material with a liquidselected such that a portion of the waste material sinks in the liquid(and another portion does not sink).

Herein throughout, the phrase “waste material” refers to substantiallysolid waste, such as municipal solid waste, which, in some embodiments,is obtained mostly from domestic sources, and is also referred to as“trash” or “garbage”. The phrase “waste material” as used hereinencompasses substantially unsorted waste material (e.g., prior toremoval of a portion of the materials as described herein), that is, itcomprises a wide variety of substances typical of domestic waste, andoptionally further encompasses waste material, as defined herein, whichhas undergone some sorting (e.g., removal of readily recyclable items).

Thus, the waste material may optionally be in the form it is received ata solid waste management facility or at a waste dump or from a landfill(referred to as “unsorted” waste material), or alternatively, wastematerial which has undergone preliminary sorting, that is, wastematerial (e.g., from the aforementioned sources) from which one or morecomponents (e.g., magnetic materials) are selectively removed (partiallyor entirely) before further sorting according to the method describedherein. The waste material may include some waste from non-domesticsources, such as sludge (e.g., sewage sludge), industrial waste (e.g.,discarded packaging material) and/or agricultural waste.

The waste material typically comprises some liquid (e.g., water, oils),for example, liquids absorbed by the waste material and/or withincontainers in the waste material. It is to be appreciated that themethod of sorting described herein is effected by contact with a liquid,so that the waste material can therefore optionally be sorted withoutany need for prior drying of the waste material.

Herein throughout, the phrase “sorted material” is used to describe amaterial obtained by removing a portion of materials in a sourcematerial (e.g., a waste material) so as to obtain a material having adifferent composition than the source material. By “source material” itis meant, for example, the waste material as described herein, which issubjected to the sorting as described herein.

Herein throughout, the term “sorting” and grammatical derivationsthereof is used to describe a process of obtaining a sorted material, asdefined herein, from a source material (e.g., a waste material), asdefined herein.

Herein throughout, the term “processing” and grammatical derivationsthereof, in the context of an act performed on a material (e.g., wastematerial), is used to describe alteration of the composition, chemicalproperties and/or physical properties of the material, to thereby obtaina different, second material, referred to herein as “processedmaterial”, having a different composition, chemical properties and/orphysical properties than the material subjected to processing. The term“processing” as used herein encompasses sorting, as defined herein, butis not limited to sorting.

For the sake of clarity, the term “processing material” is generallyused herein to describe a material obtained by procedures other thansorting (whereas a material obtained by sorting is referred to as“sorted material”), for example, by subjecting a sorted material (asdefined herein) to processing other than sorting (e.g., heating).

In some embodiments of this aspect of the present invention, the methodprovides a sorted material enriched in material having a specificgravity within a pre-selected range, and the liquid is selected inaccordance with the pre-selected range (e.g., selection of a suitableconcentration for an aqueous salt solution, as discussed in furtherdetail herein below).

In some embodiments of any of the embodiments described herein, thesorted material contains at least 90 weight percents of material havinga specific gravity within a pre-selected range. In some embodiments, thesorted material contains at least 95 weight percents of material havinga specific gravity within a pre-selected range. In some embodiments, thesorted material contains at least 98 weight percents of material havinga specific gravity within a pre-selected range. In some embodiments, thesorted material contains at least 99 weight percents of material havinga specific gravity within a pre-selected range. Any value between 90 and99.9 weight percents is also contemplated according to theseembodiments.

As used herein, the term “specific gravity” refers to a ratio of densityof a material to a density of pure water under the same conditions(e.g., temperature, pressure). Thus, the specific gravity of pure wateris defined as 1. In some embodiments of any of the embodiments describedherein, the specific gravity is a specific gravity at room temperature(e.g., 25° C.) and atmospheric pressure. However, because specificgravity is a ratio, it is less sensitive than density to changes inconditions (e.g., temperature, pressure). Hence, in some embodiments ofany of the embodiments described herein, the specific gravity is aspecific gravity under working conditions. For example, ambienttemperature under working conditions may vary, for example, within arange of about 0° C. to 50° C., and ambient pressure may vary accordingto altitude of the location.

A pre-selected range for the specific gravity may optionally becharacterized by an upper limit and a lower limit, or alternatively, therange may optionally be an open-ended range, for example, characterizedby an upper limit with no lower limit, or by a lower limit with no upperlimit.

In some embodiments of any of the embodiments described herein, thepre-selected range is no more than 1.25, that is, the upper limit of thepre-selected range is no more than 1.25, such that the entire range isno more than 1.25. In some embodiments, the pre-selected range is nomore than 1.225. In some embodiments, the pre-selected range is no morethan 1.20. In some embodiments, the pre-selected range is no more than1.175. In some embodiments, the pre-selected range is no more than 1.15.In some embodiments, the pre-selected range is no more than 1.125. Insome embodiments, the pre-selected range is no more than 1.10.

In some embodiments of any of the embodiments described herein, thesorted material is enriched (relative to the waste material from whichit is derived) in material having a specific gravity below a specificgravity of the liquid. In some of these embodiments, the method iseffected by removing materials which sink in the liquid from the wastematerial, to thereby obtain the sorted material.

In some embodiments of any of the embodiments described herein, thesorted material is enriched (relative to the waste material from whichit is derived) in material having a specific gravity above a specificgravity of the liquid. In some of these embodiments, the method iseffected by removing materials which do not sink in the liquid from thewaste material, to thereby obtain the sorted material.

In some embodiments of any of the embodiments described herein, thesorted material is enriched (relative to the waste material from whichit is derived) in material having a specific gravity below a specificgravity of a first liquid (e.g., an aqueous salt solution) and above aspecific gravity of a second liquid (e.g., water or a dilute aqueoussalt solution). In some of these embodiments, the method comprises astage of removing materials which sink in the first liquid from thewaste material, as well as a stage of removing materials which do notsink in the second liquid from the waste material.

Herein, the term “sink” encompasses sinking to a bottom of a liquid(e.g., sedimenting), as well as sinking below a surface of the liquid.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, at least a portion of the inorganicmaterials of a waste material (which are frequently denser than organicmaterials) sink to a bottom of the liquid.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, materials which sink to the bottom areremoved (e.g., by removing sediment), and substantially all othermaterials are collected.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, materials which float in the liquid arecollected (e.g., by skimming a surface of the liquid), and substantiallyall other materials are removed.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, separation of waste material comprisesremoving substantially all of the material from the liquid (e.g., boththe collected sorted material and the material removed from the wastematerial in order to obtain the sorted material removed from theliquid), such that the liquid can be reused to separate more wastematerial according to specific gravity. Removal from the liquid can befor example, by skimming floating material from a surface, removingsedimented material, and/or filtering out material which sinks below asurface of the liquid but does not sink to the bottom.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the waste material is stirred in theliquid, for example, by rotation of at least one paddle (e.g., rotationof a paddle wheel). Stirring is optionally selected to be sufficientlyvigorous to facilitate separation of different types of material (whichmay be stuck to one another, for example), while being sufficientlygentle to allow separation of materials in the liquid.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, stirring comprises perturbation (e.g.,rotation, vibration, agitation) at a frequency of 120 per minute orless. In some embodiments, stirring comprises perturbation at afrequency of 60 per minute or less. In some embodiments, stirringcomprises perturbation at a frequency of 30 per minute or less. In someembodiments, stirring comprises perturbation at a frequency of 20 perminute or less. In some embodiments, stirring comprises perturbation ata frequency of 10 per minute or less.

The liquid may be any type of liquid, including a pure liquid, asolution, and a suspension.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the liquid is an aqueous liquid.

As used herein, the phrase “aqueous liquid” refers to a liquid in whichat least 50 weight percents of the liquid compound(s) therein (e.g.,excluding solid materials suspended and/or dissolved in the liquid) iswater. In some embodiments, at least 60 weight percents is water. Insome embodiments, at least 70 weight percents is water. In someembodiments, at least 80 weight percents is water. In some embodiments,at least 90 weight percents is water. In some embodiments, at least 95weight percents is water. In some embodiments, at least 98 weightpercents is water. In some embodiments, at least 99 weight percents iswater. In some embodiments, the liquid component substantially consistsof water.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the liquid is a solution, for example, anaqueous solution. Suitable solutes for a solution (e.g., an aqueoussolution) include water-soluble salts, that is, any compound which formions in water (e.g., sodium chloride, potassium chloride, sodiumbromide, potassium bromide, calcium chloride, calcium nitrate, potassiumcarbonate) and water-soluble carbohydrates (e.g., glucose, sucrose,lactose, fructose).

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the solute is a salt, that is, the liquidis an aqueous salt solution (solution of ions). In some embodiments thesalt comprises sodium chloride. The sodium chloride may optionally besubstantially pure. Alternatively, the sodium chloride is mixed withother salts, for example, as in sea salt.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the liquid comprises sea water (e.g., seawater diluted with fresh water and/or concentrated sea water, that is,sea water from which a portion of the water has been removed). In someembodiments, the liquid consists essentially of sea water.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the liquid is a suspension, for example,an aqueous suspension. Suitable suspended materials for a suspensioninclude water-insoluble salts and/or metallic substances, such as, forexample, calcium carbonate, iron powder and ferrosilicon (FeSi). In someembodiments, the suspended material is magnetic, which facilitatesremoval its removal from separated waste materials (e.g., for reuse).

The specific gravity may be selected in accordance with the materialswhich are desired to be separated from the waste material and/or withthe materials which are desired to be retained in the waste material(e.g., for further processing).

The specific gravity of a solution or a suspension can be finelycontrolled in accordance with the separation requirements, bycontrolling the concentration of the solute or suspended material.

Thus, for example, if it is desired to separate only materials with arecharacterized by high specific gravity, a solution or suspension with arelatively high specific gravity (yet lower than that of the materialsto be separated) is to be used, and therefore, a high concentration ofthe solute or suspended material is included.

If it is desired to retain in the waste material only materials whichhave a specific gravity that is lower or is the same as that of water(e.g., organic materials), a solution or suspension with a specificgravity that is slightly above that of water is to be used, andtherefore, a relatively low concentration of the solute or suspendedmaterial in included.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, a specific gravity of the liquid is in arange of from 1.00 to 2.50.

A specific gravity of up to 2.50 may be suitable, for example, forremoving all or almost all inorganic materials which may be present inthe waste material. Thus, for example, window glass has a specificgravity of approximately 2.58, silica has a specific gravity ofapproximately 2.65, aluminum has a specific gravity of approximately2.7, and specific gravities of other minerals and metals are typicallyeven higher. In some of any of the embodiments pertaining to sortingwaste material according to specific gravity, the specific gravity ofthe liquid is at least 2.00, for example, in a range of from 2.00 to2.50. A specific of at least 2.00 may be suitable, for example, forretaining all or almost all organic materials, such as plant materials,animal materials, and polymeric materials (e.g., rubber and plastics).

Herein, “animal material” refers to material which originates from ananimal, and “plant material” refers to material which originates from aplant or fungus. It is noted that coal and petroleum products and thelike, which originate from organisms which lived only in the distantpast, are not considered herein as animal or plant material.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.50, for example, in a range of from 1.50 to 2.00. A specificgravity of at least 1.50 may be suitable, for retaining a large majorityof organic materials. In some embodiments, the specific gravity is atleast 1.60. In some embodiments, the specific gravity is at least 1.70.In some embodiments, the specific gravity is at least 1.80. In someembodiments, the specific gravity is at least 1.90.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.20, for example, in a range of from 1.20 to 1.50. A specificgravity of at least 1.20 may be suitable, for retaining many or evenmost organic materials, while removing some organic materials (e.g.,synthetic polymers). In some embodiments, the specific gravity of theliquid is at least 1.25. In some embodiments, the specific gravity ofthe liquid is at least 1.30. In some embodiments, the specific gravityof the liquid is at least 1.35. In some embodiments, the specificgravity of the liquid is at least 1.40. In some embodiments, thespecific gravity of the liquid is at least 1.45.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.01, for example, in a range of from 1.01 to 1.20. A specificgravity in a range of 1.01 to 1.20 may be suitable, for retaining manyor even most animal materials and plant materials, while removing manysynthetic polymers, such as thermoset polymers, synthetic polymershaving a melting point of at least 250° C. (e.g., polyethyleneterephthalate (PET), polytetrafluoroethylene (PTFE)) and polyvinylchloride (PVC).

Herein, the term “thermoset” refers to a synthetic polymer that has beenirreversibly cured by any technique, including curing by heating, bychemical reaction (e.g., as in epoxies) or irradiation. Examples ofthermoset polymers include, without limitation, thermoset polyesters(e.g., as used in fiberglass), polyurethanes, vulcanized rubbers,phenol-formaldehydes (e.g., Bakelite® polymer), Duroplast,urea-formaldehydes (e.g., as used in plywood), melamine resins, epoxyresins, polyimides, cyanate esters and polycyanurates.

Without being bound by any particular theory, it is believed thatreducing a proportion of thermoset polymers, synthetic polymers having ahigh melting point (e.g., at least 250° C.) and/or PVC in an obtainedsorted material renders the sorted material more amenable to processing(e.g., as described herein). It is further believed that separationaccording to specific gravity, as described herein, is a particularlyconvenient method for obtaining a sorted material with a reducedproportion of such polymers relative to a waste material from which thesorted material is derived.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is nomore than about 1.25 (e.g., about the specific gravity of a saturatedaqueous solution of sea salt). In some embodiments, the specific gravityis no more than 1.20. In some embodiments, the specific gravity is nomore than 1.15.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.05. In some embodiments, the specific gravity is in a range offrom 1.05 to 1.25. In some embodiments, the specific gravity is in arange of from 1.05 to 1.20. In some embodiments, the specific gravity isin a range of from 1.05 to 1.15.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.06. In some embodiments, the specific gravity is in a range offrom 1.06 to 1.25. In some embodiments, the specific gravity is in arange of from 1.06 to 1.20. In some embodiments, the specific gravity isin a range of from 1.06 to 1.15.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.07 (e.g., an aqueous sodium chloride solution at a concentrationof about 10 weight percents). In some embodiments, the specific gravityis in a range of from 1.07 to 1.25. In some embodiments, the specificgravity is in a range of from 1.07 to 1.20. In some embodiments, thespecific gravity is in a range of from 1.07 to 1.15.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.08. In some embodiments, the specific gravity is in a range offrom 1.08 to 1.25. In some embodiments, the specific gravity is in arange of from 1.08 to 1.20. In some embodiments, the specific gravity isin a range of from 1.08 to 1.15.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.09. In some embodiments, the specific gravity is in a range offrom 1.09 to 1.25. In some embodiments, the specific gravity is in arange of from 1.09 to 1.20. In some embodiments, the specific gravity isin a range of from 1.09 to 1.15.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.10. In some embodiments, the specific gravity is in a range offrom 1.10 to 1.25. In some embodiments, the specific gravity is in arange of from 1.10 to 1.20. In some embodiments, the specific gravity isin a range of from 1.10 to 1.15.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.11 (e.g., an aqueous sodium chloride solution at a concentrationof about 15 weight percents). In some embodiments, the specific gravityis in a range of from 1.11 to 1.25. In some embodiments, the specificgravity is in a range of from 1.11 to 1.20.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.12. In some embodiments, the specific gravity is in a range offrom 1.12 to 1.25. In some embodiments, the specific gravity is in arange of from 1.12 to 1.20.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.13. In some embodiments, the specific gravity is in a range offrom 1.13 to 1.25. In some embodiments, the specific gravity is in arange of from 1.13 to 1.20.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.14. In some embodiments, the specific gravity is in a range offrom 1.14 to 1.25. In some embodiments, the specific gravity is in arange of from 1.14 to 1.20.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.15 (e.g., an aqueous sodium chloride solution at a concentrationof about 20 weight percents). In some embodiments, the specific gravityis in a range of from 1.15 to 1.25. In some embodiments, the specificgravity is in a range of from 1.15 to 1.20.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.175. In some embodiments, the specific gravity is in a range offrom 1.175 to 1.25. In some embodiments, the specific gravity is in arange of from 1.175 to 1.20.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid is atleast 1.20. In some embodiments, the specific gravity is in a range offrom 1.20 to 1.25.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the specific gravity of the liquid isapproximately 1.03 or less, for example, in a range of from 1.01 to1.03. A specific gravity in a range may conveniently and inexpensivelybe obtained, for example, using sea water or diluted sea water, as seawater has a specific gravity in a range of from 1.02 to 1.03, typicallyapproximately 1.025.

In general, liquids with relatively low specific gravities (e.g., up to1.25, up to 1.20) are relatively convenient to prepare and use, they mayreadily be obtained from solutions of common and inexpensive materials.For example, specific gravities of aqueous sodium chloride solutionsrange from 1.00 to about 1.20, depending on concentration. Relativelylow specific gravities are particularly suitable for efficientlyremoving inorganic materials, including for example, composite materials(e.g., fiberglass and polymers with glass filler) which have a lowerspecific gravity than pure inorganic materials, as well as relativelydense organic materials such as PVC, PET, PTFE and thermoset polymers(e.g., as described herein).

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, specific gravities of at least 1.20,optionally at least 1.25, are obtained using high density water-solublesalts such as calcium salts, magnesium salts, transition metal salts,bromide salts and/or using suspensions.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, contact of waste material with a saltsolution inhibits microbial (e.g., bacterial) survival and/or activityin the obtained sorted material (in addition to facilitating the sortingprocess). Such inhibition is comparable to preservation of food in saltwater (e.g., pickling). Such inhibition may for example, enhance hygieneand/or reduce malodor of sorted material, thereby and facilitatinghandling and/or storage of the sorted material.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, a concentration of salt in a solution isselected to be capable of inhibiting microbial (e.g., bacterial)survival and/or activity in waste material contacted with the solution,and/or in sorted material and/or processed material (e.g., as describedherein) derived therefrom.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the concentration of salt (e.g., sodiumchloride, sea salt) in a salt solution (e.g., aqueous salt solution) isat least 3 weight percents. In some embodiments, the concentration ofsalt is in a range of from 3 to 35 weight percents. In some embodiments,the concentration of salt is in a range of from 3 to 30 weight percents.In some embodiments, the concentration of salt is in a range of from 3to 25 weight percents.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the concentration of salt (e.g., sodiumchloride, sea salt) in a salt solution (e.g., aqueous salt solution) isat least 5 weight percents. In some embodiments, the concentration ofsalt is in a range of from 5 to 35 weight percents. In some embodiments,the concentration of salt is in a range of from 5 to 30 weight percents.In some embodiments, the concentration of salt is in a range of from 5to 25 weight percents.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the concentration of salt (e.g., sodiumchloride, sea salt) in a salt solution (e.g., aqueous salt solution) isat least 10 weight percents. In some embodiments, the concentration ofsalt is in a range of from 10 to 35 weight percents. In someembodiments, the concentration of salt is in a range of from 10 to 30weight percents. In some embodiments, the concentration of salt is in arange of from 10 to 25 weight percents.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the concentration of salt (e.g., sodiumchloride, sea salt) in a salt solution (e.g., aqueous salt solution) isat least 15 weight percents. In some embodiments, the concentration ofsalt is in a range of from 15 to 35 weight percents. In someembodiments, the concentration of salt is in a range of from 15 to 30weight percents. In some embodiments, the concentration of salt is in arange of from 15 to 25 weight percents.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the concentration of salt (e.g., sodiumchloride, sea salt) in a salt solution (e.g., aqueous salt solution) isat least 20 weight percents. In some embodiments, the concentration ofsalt is in a range of from 20 to 35 weight percents. In someembodiments, the concentration of salt is in a range of from 20 to 30weight percents. In some embodiments, the concentration of salt is in arange of from 20 to 25 weight percents.

Without being bound by any particular theory, it is believes thatcontact of waste material with a salt solution comprising saltconcentrations of at least 10 weight percents, especially at least 15weight percents, and most especially at least 20 weight percents, isparticularly effective at inhibiting microbial (e.g., bacterial)survival and/or activity not only in waste material contacted with thesolution, but also at inhibiting microbial (e.g., bacterial) survivaland/or activity in sorted material and/or processed material (e.g., asdescribed herein) derived therefrom, that is, residual salt remaining inthe sorted material and/or processed material (after the material hasbeen removed from the salt solution) can effectively inhibit microbialsurvival and/or activity long after the separation according to specificgravity has been completed.

It is to be appreciated that cellulose and other compounds from animalmaterial or plant material (e.g., lignin) are characterized by aspecific gravity of approximately 1.5, but that animal materials andplant materials typically exhibit considerably lower specific gravitiesas a result of porosity (for, example, the voids in wood, which reducethe specific gravity of most wood to less than 1) and/or a considerableamount of water therein (which results in a specific gravity close to1). Thus, a specific gravity of many materials is indicative of itswater content and/or porosity.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, removal of materials with a relativelyhigh specific gravity (e.g., as described herein) may increase a watercontent of the material (e.g., by removing relatively dry animalmaterial and/or plant material, while retaining relatively moist animalmaterial and/or plant material), resulting in the obtained sortedmaterial having a water content higher than that of the waste material(e.g., even without absorption of water during the separation process).Thus, removal of materials as described herein may be used to increasewater content of the obtained sorted material (e.g., to a water contentdescribed herein), relative to the waste material, by facilitatingabsorption of water and/or by removing relatively dry materials.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, removal of materials with a relativelyhigh specific gravity (e.g., as described herein) may result in thesorted material having a reduced (average) specific gravity, forexample, less than 1.20, optionally less than 1.15, optionally less than1.10, optionally less than 1.05, and optionally less than 1.00.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the sorted material contains at least 90weight percents (dry weight) of an organic material, for example, byselecting a liquid in which inorganic materials sink.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the sorted material contains at least 90weight percents (dry weight) of an organic material other than thermosetpolymers and synthetic polymers having a melting point of at least 250°C. (e.g., PET, PTFE), for example, by selecting a liquid in which suchpolymers sink.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the sorted material contains at least 90weight percents (dry weight) of an organic material other than PVC, forexample, by selecting a liquid in which PVC sinks.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the sorted material contains at least 90weight percents (dry weight) of an organic material other than thermosetpolymers, synthetic polymers having a melting point of at least 250° C.(e.g., PET, PTFE) and polyvinyl chloride (PVC), for example, byselecting a liquid in which such polymers sink.

In this respect, it is to be appreciated that thermoset polymers,synthetic polymers having a melting point of at least 250° C. (e.g.,PET, PTFE) and polyvinyl chloride (PVC) are typically characterized by arelatively high specific gravity.

For example, among synthetic polymers characterized by a melting pointof at least 250° C., PET (which is particularly widespread in wastematerial, e.g., due to its use in food and liquid containers) typicallyexhibits a specific gravity in a range of from 1.37-1.455 and PTFEtypically exhibits a specific gravity in a range of 2.1-2.2.

Similarly, polyvinyl chloride (a widespread polymer) typically exhibitsa specific gravity in a range of from 1.35-1.45 in its rigid, relativelypure forms, whereas flexible forms of polyvinyl chloride typicallyexhibit a lower specific gravity (e.g., in a range of from 1.1-1.3) dueto a presence of plasticizers. Thus, a liquid with a specific gravitybelow 1.1 may be suitable for removing substantially all polyvinylchloride, whereas a liquid with a moderately higher specific gravity(e.g., in a range of from 1.1-1.3) may be suitable for removing aconsiderable proportion of polyvinyl chloride.

In addition, thermoset polymers typically comprise a considerable amountof heteroatoms (e.g., nitrogen, oxygen, sulfur), for example, in estergroups, urethane groups, and sulfur cross-links of vulcanized rubber,which increase the specific gravity of the polymer.

It is to be appreciated that contacting waste material with a liquid forseparating according to specific gravity (according to any of therespective embodiments described herein) may effect partial removal ofliquids which originate in the waste material and are miscible with theliquid for separating according to specific gravity, as the liquidsremain intermixed when a sorted material is removed from the liquids.For example, aqueous liquids in a source waste material may optionallybe at least partially removed upon contact with an aqueous liquid (e.g.,salt solution) according to any of the respective embodiments describedherein.

In addition, liquids (e.g., oils) are commonly present in the wastematerial which are immiscible with the liquid used for separatingaccording to specific gravity (e.g., an aqueous solution), and form adistinct liquid layer during the separation process, for example, alayer of oils floating on a surface of an aqueous liquid (as opposed tofloating solids which are partially submerged in the aqueous liquid).

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the method further comprises (as part ofany one or more cycles of separating materials according to specificgravity) separating at least a portion of liquids of source wastematerial (which are immiscible with the liquid for separating accordingto specific gravity) from the other waste material and from the liquidfor separating according to specific gravity. In some embodiments, oilsin the source waste material which float on a surface of an aqueousliquid (e.g., salt solution) for separating according to specificgravity are separated.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the sorted material has a lowerconcentration of oils than does the waste material prior to sorting.

Herein, the term “oil” refers to a liquid which is immiscible withwater, and encompasses substances which are liquid at a temperature in arange of 0° C. to 100° C.

In some embodiments of any of the embodiments described herein, the oilsare liquid at a temperature in a range of 0° C. to 50° C. In someembodiments of any of the embodiments described herein, the oils are aliquid at 20° C.

Herein, the phrase “immiscible with water” means that for at least someproportions of water and another liquid (e.g., an oil as definedherein), the liquid and the water do not form a homogeneous solutionwith one another, and separate into distinct phases.

In some embodiments of any of the embodiments described herein, the oilis composed of compounds characterized by a log P (logarithm of apartition coefficient) of at least 1. In some embodiments, the log P ofcompounds in the oil is at least 1.5. In some embodiments, the log P ofcompounds in the oil is at least 2.

Herein, the term “log P” refers to a logarithm of a ratio of aconcentration of a compound in 1-octanol to a concentration of thecompound in water, upon contact of the compound with a combination of1-octanol and water (which form separate phases). The concentrationspertain to compounds in an unionized form.

Removal of immiscible liquids according to any of the respectiveembodiments described herein may optionally be performed using standardtechniques known in the art. For example, a layer of oil may be skimmedfrom a surface of an aqueous solution using a weir skimmer, and/or anoleophobic and/or metallic skimmer (e.g., using a rotating element suchas a drum, rope, disc and/or belt to adhere to and remove oils). Theskimmers (of any type) are optionally configured to cease skimming whenoil is not present in sufficient quantities to be skimmed effectively.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, oils separated from the liquid forseparating according to specific gravity (e.g., by skimming the oilsfrom a surface of the liquid) are collected, for example, for use as araw ingredient for further processing of oils.

Alternatively or additionally, separation of the oils may be in order toobtain a sorted material with less oil, and/or to reducing levels of oilimpurities in the liquids used in a process described herein. In somesuch embodiments, the separated oils are discarded.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the oils comprise lipids released fromcells in the waste material during the separation process, for example,upon contact with an aqueous salt solution (e.g., a hypertonic solution)which subjects the cells to osmotic stress.

Removal of materials may optionally be performed before and/or aftershredding, and/or during shredding (e.g., between two stages ofshredding).

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the waste material is a shredded wastematerial, that is, obtained in a shredded form, for example, wastematerial has been subjected to crushing (e.g., by a hammer mill). Insome embodiments, the shredded waste material is further shredded asdescribed herein.

As used herein, the terms “shred”, “shredded” and “shredding” and thefurther grammatical diversions thereof refer to reduction in size of thesolid components of material (e.g., waste material, sorted material) byany mechanical means, including chopping, dicing, grinding, crumbling,cutting, tearing and crushing.

A variety of devices are available in the art for shredding wastematerial, including, without limitation, industrial shredders, grinders,chippers and granulators. Optionally, the device used for shredding isdesigned to be suitable for handling the presence of hard substancessuch as metal, glass, clay and stone in waste material, for example, byusing blades or plates made of robust materials such as stainless steelor titanium.

Herein, the term “shredder” encompasses all devices configured forshredding, as defined herein.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, waste material is shredded prior toremoval of materials by contacting with a liquid (e.g., as describedherein for, for example, sorting), for example, so as to facilitateseparation of different types of material which are attached to oneanother (e.g., metal attached to plastic) and/or to facilitate escape ofgases and entry of liquid to crevices in particles of waste material. Insome embodiments, solid particles in the shredded material are less than50 mm in diameter, optionally less than 20 mm in diameter, whenmaterials are removed. In some embodiments, the solid particles are lessthan 10 mm in diameter when materials are removed.

In some embodiments, shredding prior to removal of materials is effectedby hammers (e.g., crushing), for example, by a hammer mill.

Without being bound by any particular theory, it is believed thathammers are relatively resistant to damage associated with a presence ofhard materials (e.g., inorganic materials such as mineral, ceramic,glass, metal) in waste material which has not yet been subjected toremoval of such materials.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, a sorted material is shredded subsequentto removal of materials by contacting with a liquid (e.g., by shreddingto a particle size described herein), for example, so as to remove hardand dense materials (e.g., inorganic materials) which may damage anapparatus effecting shredding, and/or so that particles of the wastematerial will not be so small as to interfere with removal of materials.For example, small particles generally separate according to specificgravity more slowly than do large particles. In some embodiments, thesolid particles are at least 2 mm in diameter when materials areremoved. In some embodiments, the solid particles are at least 5 mm indiameter when materials are removed. In some embodiments, the solidparticles are at least 10 mm in diameter when materials are removed.

In some embodiments of any of the embodiments described herein relatingto shredding, shredding subsequent to removal of materials is effectedby cutting (e.g., by blades and/or plates), for example, in anindustrial shredder.

Without being bound by any particular theory, it is believed that such ashredding technique is particularly suitable for forming relativelysmall particles, which may be more suitable for further processing(e.g., by mixing and heating as described herein), but may be relativelysusceptible to hard and dense materials (e.g., inorganic materials), andtherefore suitable for sorted material which has a reduced amount ofsuch materials.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, waste material is shredded prior toremoval of materials to a relatively large particle size (e.g., at least10 mm in diameter), for example, using crushing, hammers and/or similartechniques. Subsequent to removal of materials, the sorted material isthen optionally further shredded to smaller particles of a size (e.g.,less than 10 mm in diameter) selected as suitable for further processing(e.g., mixing and heating as described herein).

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the method comprises more than one cycleof separating materials according to specific gravity.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the waste material is contacted with anaqueous liquid (e.g., as described herein) to thereby obtain a partiallysorted material, and the partially sorted waste material is furthersubjected to at least one additional cycle of separating materialsaccording to specific gravity. In each of the aforementioned at leastone additional cycle, the separating comprises contacting the partiallysorted waste material with an additional liquid (e.g., a liquiddescribed herein for separating materials).

Herein, the phrase “partially sorted material” refers to a sortedmaterial, as defined herein, which is intended to be subjected tofurther sorting. Thus, the phrase “sorted material” encompasses“partially sorted material”.

It is to be understood that each cycle may be effected with a liquid(e.g., an aqueous salt solution) which is the same or different than aliquid (e.g., an aqueous salt solution) used in another cycle, and thateach cycle may independently comprise removing the high-densitymaterials (e.g., materials which sink in the liquid) from the wastematerial or removing the low-density materials (e.g., materials whichfloat in the liquid) from the waste material.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, at least one cycle of separatingmaterials according to specific gravity comprises removing materialwhich sinks in the liquid of that cycle. In some embodiments, at leastone cycle other than the first cycle (i.e., at least one additionalcycle) comprises removing material which sinks in the liquid of thatcycle (i.e., an additional liquid described herein). In someembodiments, a first cycle comprises removing material which sinks inthe liquid of that cycle. In some embodiments, a first cycle and atleast one additional cycle comprises removing material which sinks inthe liquid of that cycle.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, at least one cycle of separatingmaterials according to specific gravity comprises removing materialwhich floats in the liquid of that cycle. In some embodiments, a firstcycle comprises removing material which sinks in the liquid of thatcycle, and at least one later cycle comprises removing material whichfloats in the liquid of that cycle.

Each cycle may be independently optionally further comprise shreddingthe obtained sorted material (optionally partially sorted material aftercycles other than the final cycle) subsequent to contact with the liquidof that cycle (e.g., as described herein). In some embodiments of any ofthe embodiments pertaining to sorting waste material, at least one cycleother than the first cycle (i.e., at least one additional cycle) furthercomprises shredding of the sorted material subsequent to contact withthe liquid of that cycle (i.e., an additional liquid described herein).In some embodiments, the final cycle comprises shredding of the sortedmaterial (i.e., after contact with the liquid of the final cycle). Insome embodiments, each cycle comprises shredding of the obtained sortedmaterial (including partially sorted material after cycles other thanthe final cycle).

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, removal of liquid is performed subsequentto at least one cycle of separating materials according to specificgravity. The removal of liquid may optionally be effected by drainage(e.g., gravity-driven drainage) and/or compression of the sortedmaterial, for example, using a screw press. Optionally, at least aportion of the removed liquid is reused for separating materials asdescribed herein.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, removed liquid comprises liquid whichoriginates in the waste material, for example, aqueous liquids and/oroils. For example, liquid removed according to any of the respectiveembodiments described herein (e.g., by drainage and/or compression) mayoptionally comprise an aqueous liquid (e.g., salt solution) used forseparating according to specific gravity (according to any of therespective embodiments described herein), as well as aqueous liquidoriginating in the waste material which is intermixed with the aqueousliquid for separating according to specific gravity, and/or oilsoriginating in the waste material.

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, separation of oils from the removedliquid is performed, for example, in order to collect oils for furtherprocessing, and/or to facilitate reuse of a liquid (e.g., aqueousliquid) for separating materials by reducing levels of oil impurities.

Separation of oils from the removed liquid may be performed according totechniques and apparatuses known in the art, for example,electrochemical emulsification; bioremediation; oil-water separatorsknown in the art, including, without limitation, gravity oil-waterseparators (e.g., API separators, gravity plate separators) andcentrifugal oil-water separators; and/or a skimmer (e.g., any skimmerdescribed herein).

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, the method comprises both collecting oilsseparated from the liquid for separating according to specific gravity(e.g., by skimming the oils from a surface of the liquid) according toany of the respective embodiments described herein, as well ascollecting oils separated from removed liquid according to any of therespective embodiments described herein, and combining the collectedoils, for example, for further processing. That is, in such embodiments,oil is collected both during at least one cycle of separating materials(wherein waste material is contacted with a liquid), and subsequent toat least one cycle of separating materials (wherein liquid is removedfrom sorted material, and oils are separated from the removed liquid).

In some of any of the embodiments pertaining to sorting waste materialaccording to specific gravity, separated materials (e.g., inorganicmaterials) are further sorted (e.g., using techniques known in the art)so as to extract useful and/or valuable materials such as metals (e.g.,iron, gold) and silica and/or glass (e.g., for use as filler inconcrete, plastics, and the like).

It is to be noted that the removal of materials as described hereinaffects the chemical composition of the end product (e.g., a processedmaterial obtained by processing the sorted material as described herein)and that the selection of the liquid used in any of these embodimentscan be made also in accordance with the desired characteristics of theend product, so as to retain in the waste material materials of achemical composition that would impart the desired characteristics ofthe end product.

For example, the dry weight of a representative domestic waste materialmay comprise about 60% of wood-derived materials (e.g., paper,cardboard, branches) containing lignin, typically in the form oflignocellulose; about 20% of organic materials without lignin (e.g.,plastics, non-woody plant-derived material such as food); and about 20%of inorganic materials (e.g., stone, sand, glass, ceramic, metal). Theproportion of lignocellulose-containing materials (e.g., materialscontaining lignin, cellulose and/or hemicellulose) is expected toincrease upon removal of dense materials such as inorganic materialsand/or polymers such as thermoset polymers, PET and PVC from the wastematerial, as described herein.

The sorted material obtained as described herein is particularlyamenable to further processing according to procedures uncovered by thepresent inventor and described herein. Furthermore, such procedures areparticularly suitable for processing wet material, such as wastematerial sorted by contact with a liquid (e.g., as described herein).Thus, the sorting and further processing may be combined as aparticularly efficient and effective method of processing wastematerial.

In some of any of the embodiments pertaining to separating materialsaccording to specific gravity as described herein, removal of inorganicmaterials in the waste material is such that an obtained sorted materialcontains at least 90 weight percents (dry weight) of an organicmaterial. In some embodiments, the sorted material contains at least 95weight percents (dry weight) of an organic material. In someembodiments, the sorted material contains at least 98 weight percents(dry weight) of an organic material. In some embodiments, the sortedmaterial contains at least 99 weight percents (dry weight) of an organicmaterial.

In some of any of the embodiments pertaining to separating materialsaccording to specific gravity as described herein, the method comprisesremoving at least a portion of certain organic materials (e.g.,synthetic polymers, as defined herein) in the waste. In someembodiments, the method comprises removing at least a portion ofpolyvinyl chloride, synthetic polymers having a relatively high meltingpoint (e.g., at least 250° C.) and/or thermoset polymers (e.g., asdescribed herein).

In some of any of the embodiments pertaining to separating materialsaccording to specific gravity as described herein, the sorted materialcontains at least 90 weight percents (dry weight) of an organic materialother than thermoset polymers and synthetic polymers having a meltingpoint of at least 250° C. In some embodiments, the sorted materialcontains at least 95 weight percents (dry weight) of an organic materialother than thermoset polymers and synthetic polymers having a meltingpoint of at least 250° C. In some embodiments, the sorted materialcontains at least 98 weight percents (dry weight) of an organic materialother than thermoset polymers and synthetic polymers having a meltingpoint of at least 250° C. In some embodiments, the sorted materialcontains at least 99 weight percents (dry weight) of an organic materialother than thermoset polymers and synthetic polymers having a meltingpoint of at least 250° C.

In some of any of the embodiments pertaining to separating materialsaccording to specific gravity as described herein, the sorted materialcontains at least 90 weight percents (dry weight) of an organic materialother than PVC. In some embodiments, the sorted material contains atleast 95 weight percents (dry weight) of an organic material other thanPVC. In some embodiments, the sorted material contains at least 98weight percents (dry weight) of an organic material other than PVC. Insome embodiments, the sorted material contains at least 99 weightpercents (dry weight) of an organic material other than PVC.

In some of any of the embodiments pertaining to separating materialsaccording to specific gravity as described herein, the sorted materialcontains at least 90 weight percents (dry weight) of an organic materialother than PVC, thermoset polymers and synthetic polymers having amelting point of at least 250° C. In some embodiments, the sortedmaterial contains at least 95 weight percents (dry weight) of an organicmaterial other than PVC, thermoset polymers and synthetic polymershaving a melting point of at least 250° C. In some embodiments, thesorted material contains at least 98 weight percents (dry weight) of anorganic material other than PVC, thermoset polymers and syntheticpolymers having a melting point of at least 250° C. In some embodiments,the sorted material contains at least 99 weight percents (dry weight) ofan organic material other than PVC, thermoset polymers and syntheticpolymers having a melting point of at least 250° C.

In some of any of the embodiments pertaining to separating materialsaccording to specific gravity as described herein, no more than 5 weightpercents of the dry weight of the sorted material is inorganic material.In some embodiments, no more than 4 weight percents is inorganicmaterial. In some embodiments, no more than 3 weight percents isinorganic material. In some embodiments, no more than 2 weight percentsis inorganic material. In some embodiments, no more than 1 weightpercent is inorganic material. In some embodiments, no more than 0.5weight percent is inorganic material. In some embodiments, no more than0.2 weight percent is inorganic material. In some embodiments, no morethan 0.1 weight percent is inorganic material.

Herein, wherever an amount of “inorganic material” in a sorted materialand/or feedstock is described, the amount does not include any inorganicwater-soluble salt and/or ions included in an aqueous liquid used forseparation as described herein.

Without being bound by any particular theory, it is believed that suchsalts do not have a substantial deleterious effect, and may even have abeneficial effect, on further processing of the sorted material, whereasother inorganic materials are likely to have a deleterious effect (e.g.,as described herein), and hence, it is advantageous to reduce an amountof such inorganic material.

As described in detail herein, the sorted material obtained as describedherein is particularly amenable to further processing. The sortedmaterial may optionally be subjected to further processing as is, or maybe used to prepare a feedstock intended for processing.

Without being bound by any particular theory, it is believed that thesorted material obtained as described herein is particularly amenable toprocessing comprising moderate heating, mixing and/or extrusion, asmaterials which are less amenable to such processing, such as materialswhich do not melt or substantially soften at such temperatures (e.g.,inorganic materials, thermoset polymers, polymers having a relativelyhigh melting point), materials which form toxic products upon heating atsuch temperatures (e.g., polyvinylchloride), highly abrasive materials(e.g., hard inorganic materials) and materials which tend to causeclogging (including, but not limited to, materials which do not melt orsubstantially soften upon heating at such temperatures).

Furthermore, procedures described herein are particularly suitable forprocessing wet material, such as waste material sorted by contact with aliquid (e.g., as described herein).

Furthermore, the sorted material obtained as described hereinfacilitates recycling of waste material by removing materials which arenot amenable to recycling, such as toxic metals and minerals (e.g.,arsenic, cadmium, cobalt, chromium, mercury, nickel, lead, antimony,selenium, asbestos), and materials which are typically not recycled dueto formation of toxic products upon heating (e.g., polyvinylchloride).

Thus, the sorting and further processing may be combined as aparticularly efficient and effective method of processing wastematerial.

Hence, according to an aspect of some embodiments of the presentinvention, there is provided a method of processing waste material so asto form a non-particulate processed material. The method comprisesproviding a feedstock comprising a sorted material derived from a wastematerial (e.g., as described herein). In some embodiments of theembodiments pertaining to a method of processing waste material asdescribed herein, the method is effected by subjecting the feedstock tomixing via shear forces, and subjecting the feedstock to heating, tothereby obtain a processed material. The feedstock is preferablysubjected to the mixing and the heating without being dried beforehand.

Thus, in some embodiments of any of the embodiments described herein,the method of processing waste material as described herein incorporatesa method of sorting waste material according to any one of theembodiments described herein pertaining to separating materialsaccording to specific gravity as described herein.

Herein, the term “feedstock” refers to a material subjected toprocessing (material that is processed) by heating and/or mixing asdescribed herein, except where indicated otherwise. The feedstock mayconsist of a sorted material as described herein, in any one of therespective embodiments, or may be different than the sorted material,for example, when a feedstock comprises a sorted material in combinationwith one or more additional materials (e.g., as described herein).

In some embodiments of the embodiments pertaining to a method ofprocessing waste material as described herein, the term “feedstock”encompasses a sorted material as described herein. In some embodiments,the term “feedstock” describes a sorted material as described hereincombined (e.g., mixed) with one or more additional materials, asdescribed herein.

Herein, the term “non-particulate” refers to a solid material which isnot composed of discrete particles (e.g., particles adhered to oneanother, or optionally aggregates thereof) having a volume of more than0.2 mm³, that is, the material is not formed of particles of theaforementioned volume characterized by visible boundaries and/orparticles consisting of different substances than their adjacentsurroundings. In some embodiments of the embodiments pertaining to amethod of processing waste material as described herein, thenon-particulate material is not composed of discrete particles having avolume of more than 0.04 mm³. In some embodiments, the non-particulatematerial is not composed of discrete particles having a volume of morethan 0.01 mm³. It is to be understood that a non-particulate materialmay comprise some discrete particles embedded therein, but that the bulkof the material comprises a continuous non-particulate matrix.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, less than 20 weight percents of thenon-particulate processed material consists of discrete particles. Insome embodiments, less than 10 weight percents of the non-particulateprocessed material consists of discrete particles. In some embodiments,less than 5 weight percents of the non-particulate processed materialconsists of discrete particles. In some embodiments, less than 2 weightpercents of the non-particulate processed material consists of discreteparticles. In some embodiments, less than 1 weight percents of thenon-particulate processed material consists of discrete particles.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, heating is performed subsequent tomixing. In some embodiments, heating is performed prior to mixing. Insome embodiments, the feedstock is subjected to mixing and heatingsimultaneously.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 50 weight percents of thedry weight of the feedstock is a sorted material obtained by separatingmaterials in a waste material according to specific gravity, asdescribed herein. In some embodiments, at least 60 weight percents ofthe dry weight of the feedstock is a sorted material. In someembodiments, at least 70 weight percents of the dry weight of thefeedstock is a sorted material. In some embodiments, at least 80 weightpercents of the dry weight of the feedstock is a sorted material. Insome embodiments, at least 90 weight percents of the dry weight of thefeedstock is a sorted material. In some embodiments, at least 95 weightpercents of the dry weight of the feedstock is a sorted material. Insome embodiments, at least 98 weight percents of the dry weight of thefeedstock is a sorted material. In some embodiments, at least 99 weightpercents of the dry weight of the feedstock is a sorted material. Insome embodiments, substantially all of the dry weight of the feedstockis a sorted material.

Herein, descriptions of a feedstock and/or a composition thereof, referto a feedstock prior to mixing and heating, except where indicatedotherwise.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, the feedstock (prior to mixing andheating) has a water content of at least 15 weight percents. In someembodiments, the feedstock has a water content of at least 20 weightpercents. In some embodiments, the feedstock has a water content of atleast 30 weight percents. In some embodiments, the feedstock has a watercontent of at least 40 weight percents. In some embodiments, thefeedstock has a water content of at least 45 weight percents. In someembodiments, the feedstock has a water content of at least 50 weightpercents. In some embodiments, the feedstock has a water content of atleast 55 weight percents. In some embodiments, the feedstock has a watercontent of at least 60 weight percents.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, the feedstock (prior to mixing andheating) has a water content of from 15 to 70 weight percents. In someembodiments, the feedstock has a water of from 20 to 70 weight percents.In some embodiments, the feedstock has a water content of from 30 to 70weight percents. In some embodiments, the feedstock has a water contentof from 40 to 70 weight percents. In some embodiments, the feedstock hasa water content of from 45 to 70 weight percents. In some embodiments,the feedstock has a water content of from 50 to 70 weight percents. Insome embodiments, the feedstock has a water content of from 55 to 70weight percents. In some embodiments, the feedstock has a water contentof from 60 to 70 weight percents. In some embodiments, the feedstock hasa water content of about 64 weight percents.

The origin of water in the feedstock may optionally be the water contentof a waste material, an aqueous liquid used for separation according tospecific gravity (e.g., as described herein), and/or water added to asorted material.

In some embodiments of any of the embodiments pertaining to processingwaste material described herein, the feedstock has a water content whichis higher than that of a waste material from which it is derived. Forexample, the contact of waste material with an aqueous liquid duringseparation according to specific gravity as described may result in asorted material (which is then comprised by the feedstock) having awater content which is higher than that of a waste material from whichit is derived (e.g., due to absorption of the aqueous liquid).Additionally or alternatively, water is added to the sorted material toproduce the feedstock. Thus, the feedstock may optionally have a watercontent which is higher than that of the sorted material.

It is to be appreciated that the use of an aqueous liquid to separatematerials is particularly suitable in the context of a method suitablefor utilizing a feedstock having a relatively high water content (e.g.,as described herein), as the incorporation of water from the aqueousliquid into the sorted material is not necessarily a problem when usingsuch a feedstock.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 20 weight percents of thedry weight of the feedstock is lignocellulose. In some embodiments, from20 to 95 weight percents of the dry weight is lignocellulose. In someembodiments, from 20 to 90 weight percents of the dry weight islignocellulose. In some embodiments, from 20 to 85 weight percents ofthe dry weight is lignocellulose. In some embodiments, from 20 to 80weight percents of the dry weight is lignocellulose. In someembodiments, from 20 to 70 weight percents of the dry weight islignocellulose. In some embodiments, from 20 to 60 weight percents ofthe dry weight is lignocellulose. In some embodiments, from 20 to 50weight percents of the dry weight is lignocellulose. In someembodiments, at least 40 weight percents of the lignocelluloses iscarbohydrates. In some embodiments, at least 60 weight percents of thelignocelluloses is carbohydrates. In some embodiments, at least 80weight percents of the lignocelluloses is carbohydrates. In someembodiments, at least 90 weight percents of the lignocelluloses iscarbohydrates.

As used herein, the term “lignocellulose” refers to dry matter derivedfrom plants, which is composed primarily of carbohydrates (primarilycellulose and hemicelluloses) and lignin. Thus, an amount oflignocellulose described herein may be considered a total amount of drymatter derived from plants, regardless of the proportions of, e.g.,carbohydrates and lignin.

Without being bound by any particular theory, it is believed that thecarbohydrates in lignocelluloses (e.g., cellulose and/or hemicelluloses)are particularly amenable to processing as described herein (e.g., ascompared to lignin) and provide desirable properties to the obtainedprocess material. The proportion of carbohydrates in the lignocellulosemay optionally be enhanced by limiting an amount of lignin-rich materialin the waste material being processed, for example, by using wastematerial with no more than a limited amount of wood (e.g., treetrimmings, lumberyard waste).

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 30 weight percents of thedry weight of the feedstock is lignocellulose. In some embodiments, from30 to 95 weight percents of the dry weight is lignocellulose. In someembodiments, from 30 to 90 weight percents of the dry weight islignocellulose. In some embodiments, from 30 to 85 weight percents ofthe dry weight is lignocellulose. In some embodiments, from 30 to 80weight percents of the dry weight is lignocellulose. In someembodiments, from 30 to 70 weight percents of the dry weight islignocellulose. In some embodiments, from 30 to 60 weight percents ofthe dry weight is lignocellulose. In some embodiments, from 30 to 50weight percents of the dry weight is lignocellulose. In someembodiments, at least 40 weight percents of the lignocelluloses iscarbohydrates. In some embodiments, at least 60 weight percents of thelignocelluloses is carbohydrates. In some embodiments, at least 80weight percents of the lignocelluloses is carbohydrates. In someembodiments, at least 90 weight percents of the lignocelluloses iscarbohydrates.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 40 weight percents of thedry weight of the feedstock is lignocellulose. In some embodiments, from40 to 95 weight percents of the dry weight is lignocellulose. In someembodiments, from 40 to 90 weight percents of the dry weight islignocellulose. In some embodiments, from 40 to 85 weight percents ofthe dry weight is lignocellulose. In some embodiments, from 40 to 80weight percents of the dry weight is lignocellulose. In someembodiments, from 40 to 70 weight percents of the dry weight islignocellulose. In some embodiments, from 40 to 60 weight percents ofthe dry weight is lignocellulose. In some embodiments, at least 40weight percents of the lignocelluloses is carbohydrates. In someembodiments, at least 60 weight percents of the lignocelluloses iscarbohydrates. In some embodiments, at least 80 weight percents of thelignocelluloses is carbohydrates. In some embodiments, at least 90weight percents of the lignocelluloses is carbohydrates.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 50 weight percents of thedry weight of the feedstock is lignocellulose. In some embodiments, from50 to 95 weight percents of the dry weight is lignocellulose. In someembodiments, from 50 to 90 weight percents of the dry weight islignocellulose. In some embodiments, from 50 to 85 weight percents ofthe dry weight is lignocellulose. In some embodiments, from 50 to 80weight percents of the dry weight is lignocellulose. In someembodiments, from 50 to 75 weight percents of the dry weight islignocellulose. In some embodiments, from 50 to 70 weight percents ofthe dry weight is lignocellulose. In some embodiments, at least 40weight percents of the lignocelluloses is carbohydrates. In someembodiments, at least 60 weight percents of the lignocelluloses iscarbohydrates. In some embodiments, at least 80 weight percents of thelignocelluloses is carbohydrates. In some embodiments, at least 90weight percents of the lignocelluloses is carbohydrates.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 60 weight percents of thedry weight of the feedstock is lignocellulose. In some embodiments, from60 to 95 weight percents of the dry weight is lignocellulose. In someembodiments, from 60 to 90 weight percents of the dry weight islignocellulose. In some embodiments, from 60 to 85 weight percents ofthe dry weight is lignocellulose. In some embodiments, from 60 to 80weight percents of the dry weight is lignocellulose. In someembodiments, at least 40 weight percents of the lignocelluloses iscarbohydrates. In some embodiments, at least 60 weight percents of thelignocelluloses is carbohydrates. In some embodiments, at least 80weight percents of the lignocelluloses is carbohydrates. In someembodiments, at least 90 weight percents of the lignocelluloses iscarbohydrates.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 70 weight percents of thedry weight of the feedstock is lignocellulose. In some embodiments, from70 to 95 weight percents of the dry weight is lignocellulose. In someembodiments, from 70 to 90 weight percents of the dry weight islignocellulose. In some embodiments, from 70 to 85 weight percents ofthe dry weight is lignocellulose. In some embodiments, from 75 to 85weight percents of the dry weight is lignocellulose. In someembodiments, from 80 to 85 weight percents of the dry weight islignocellulose. In some embodiments, at least 40 weight percents of thelignocelluloses is carbohydrates. In some embodiments, at least 60weight percents of the lignocelluloses is carbohydrates. In someembodiments, at least 80 weight percents of the lignocelluloses iscarbohydrates. In some embodiments, at least 90 weight percents of thelignocelluloses is carbohydrates.

Typically, the feedstock will comprise at least a portion of thesynthetic polymers in the waste material, which are present in thesorted material. In addition, the feedstock may optionally comprisesynthetic polymers added to the sorted material (e.g., an additionalmaterial described herein).

Herein, the phrase “synthetic polymers” refers to polymers other thanthose found in plant or animal material (e.g., lignin, carbohydrates,polypeptides) or polymers formed from heating and mixing plant or animalmaterial as described herein (e.g., products of hydrolysis,caramelization and/or pyrolysis of carbohydrates, polypeptides, etc.).Examples of synthetic polymers include, without limitation, polyolefins,polystyrene, polyvinylchloride, polyethylene terephthalate,polyacrylonitrile, polybutadiene, polystyrene, polycarbonate, polyesters(e.g., rayon), and nylon. Polymers formed by chemical reactions of anatural polymer, for example, cellulose which has been chemicallytreated (e.g., by carbon disulfide) and regenerated to form rayon, areconsidered herein to be synthetic polymers. The skilled person will beaware of additional synthetic polymers which may be found in wastematerial, and which consequently may be included in the feedstockdescribed herein.

Without being bound by any particular theory, it is believed thatpolyolefins will comprise a substantial portion of the syntheticpolymers in the sorted material and feedstock, due to the relatively lowspecific gravity of polyolefins. In addition, the feedstock mayoptionally further comprise synthetic polymers added to the sortedmaterial.

Herein, the term “polyolefin” refers to a polymer prepared from anolefin monomer. Examples of polyolefins include, without limitation,polyethylene, polypropylene, polymethylpentene, polybutene-1,polyisobutylene, ethylene propylene rubber, ethylene propylene dienemonomer rubber, and copolymers thereof. Polyethylene and polypropyleneare particularly common in waste material, and therefore likely to bepresent in substantial amounts in the sorted material and feedstock.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 50 weight percents of thesynthetic polymers is polyolefins. In some embodiments, at least 60weight percents of the synthetic polymers is polyolefins. In someembodiments, at least 70 weight percents of the synthetic polymers ispolyolefins. In some embodiments, at least 80 weight percents of thesynthetic polymers is polyolefins. In some embodiments, at least 90weight percents of the synthetic polymers is polyolefins.

Without being bound by any particular theory, it is believed thatthermoplastic polymers will comprise a substantial portion of thesynthetic polymers in the sorted material and feedstock, due to therelatively low specific gravity of many thermoplastic polymers,including, but not limited to thermoplastic polyolefins (e.g.,polyethylene, polypropylene, polymethylpentene, polybutene-1). Inaddition, the feedstock may optionally further comprise thermoplasticpolymers added to the sorted material. It is further believed thatthermoplastic polymers, particularly thermoplastic synthetic polymers,undergo softening and/or melting upon mixing and heating as describedherein, which allows for a more homogeneous processed material.

Furthermore, the presence of one or more thermoplastic syntheticpolymers may optionally enhance the thermoplasticity of the processedmaterial (e.g., a polymeric material described herein), and/or allow forrecycling of the synthetic polymer.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 50 weight percents of thesynthetic polymers is thermoplastic. In some embodiments, at least 60weight percents of the synthetic polymers is thermoplastic. In someembodiments, at least 70 weight percents of the synthetic polymers isthermoplastic. In some embodiments, at least 80 weight percents of thesynthetic polymers is thermoplastic. In some embodiments, at least 90weight percents of the synthetic polymers is thermoplastic. In someembodiments, at least 95 weight percents of the synthetic polymers isthermoplastic.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 5 weight percents of thedry weight of the feedstock comprises or is consisted of syntheticpolymers. In some embodiments, from 5 to 80 weight percents of the dryweight comprises or is consisted of synthetic polymers. In someembodiments, from 5 to 70 weight percents of the dry weight comprises oris consisted of synthetic polymers. In some embodiments, from 5 to 60weight percents of the dry weight comprises or is consisted of syntheticpolymers. In some embodiments, from 5 to 50 weight percents of the dryweight comprises or is consisted of synthetic polymers. In someembodiments, from 5 to 40 weight percents of the dry weight comprises oris consisted of synthetic polymers. In some embodiments, from 5 to 30weight percents of the dry weight comprises or is consisted of syntheticpolymers. In some embodiments, from 5 to 25 weight percents of the dryweight comprises or is consisted of synthetic polymers. In someembodiments, from 5 to 20 weight percents of the dry weight comprises oris consisted of synthetic polymers. In some embodiments, from 5 to 15weight percents of the dry weight comprises or is consisted of syntheticpolymers. In some embodiments, at least 50 weight percents of thesynthetic polymers comprises or is consisted of polyolefins. In someembodiments, at least 60 weight percents of the synthetic polymerscomprises or is consisted of polyolefins. In some embodiments, at least70 weight percents of the synthetic polymers comprises or is consistedof polyolefins. In some embodiments, at least 80 weight percents of thesynthetic polymers comprises or is consisted of polyolefins. In someembodiments, at least 90 weight percents of the synthetic polymerscomprises or is consisted of polyolefins.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 10 weight percents of thedry weight of the feedstock comprises or is consisted of syntheticpolymers. In some embodiments, from 10 to 80 weight percents of the dryweight comprises or is consisted of synthetic polymers. In someembodiments, from 10 to 70 weight percents of the dry weight comprisesor is consisted of synthetic polymers. In some embodiments, from 10 to60 weight percents of the dry weight comprises or is consisted ofsynthetic polymers. In some embodiments, from 10 to 50 weight percentsof the dry weight comprises or is consisted of synthetic polymers. Insome embodiments, from 10 to 40 weight percents of the dry weightcomprises or is consisted of synthetic polymers. In some embodiments,from 10 to 30 weight percents of the dry weight comprises or isconsisted of synthetic polymers. In some embodiments, from 10 to 25weight percents of the dry weight comprises or is consisted of syntheticpolymers. In some embodiments, from 10 to 20 weight percents of the dryweight comprises or is consisted of synthetic polymers. In someembodiments, from 10 to 15 weight percents of the dry weight comprisesor is consisted of synthetic polymers. In some embodiments, at least 50weight percents of the synthetic polymers comprises or is consisted ofpolyolefins. In some embodiments, at least 60 weight percents of thesynthetic polymers comprises or is consisted of polyolefins. In someembodiments, at least 70 weight percents of the synthetic polymerscomprises or is consisted of polyolefins. In some embodiments, at least80 weight percents of the synthetic polymers comprises or is consistedof polyolefins. In some embodiments, at least 90 weight percents of thesynthetic polymers is polyolefins.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 15 weight percents of thedry weight of the feedstock is synthetic polymers. In some embodiments,from 15 to 80 weight percents of the dry weight comprises or isconsisted of synthetic polymers. In some embodiments, from 15 to 70weight percents of the dry weight comprises or is consisted of syntheticpolymers. In some embodiments, from 15 to 60 weight percents of the dryweight comprises or is consisted of synthetic polymers. In someembodiments, from 15 to 50 weight percents of the dry weight comprisesor is consisted of synthetic polymers. In some embodiments, from 15 to40 weight percents of the dry weight comprises or is consisted ofsynthetic polymers. In some embodiments, from 15 to 30 weight percentsof the dry weight comprises or is consisted of synthetic polymers. Insome embodiments, from 15 to 25 weight percents of the dry weightcomprises or is consisted of synthetic polymers. In some embodiments,from 15 to 20 weight percents of the dry weight comprises or isconsisted of synthetic polymers. In some embodiments, at least 50 weightpercents of the synthetic polymers comprises or is consisted ofpolyolefins. In some embodiments, at least 60 weight percents of thesynthetic polymers comprises or is consisted of polyolefins. In someembodiments, at least 70 weight percents of the synthetic polymerscomprises or is consisted of polyolefins. In some embodiments, at least80 weight percents of the synthetic polymers comprises or is consistedof polyolefins. In some embodiments, at least 90 weight percents of thesynthetic polymers is polyolefins.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 20 weight percents of thedry weight of the feedstock is synthetic polymers. In some embodiments,from 20 to 80 weight percents of the dry weight comprises or isconsisted of synthetic polymers. In some embodiments, from 20 to 70weight percents of the dry weight comprises or is consisted of syntheticpolymers. In some embodiments, from 20 to 60 weight percents of the dryweight comprises or is consisted of synthetic polymers. In someembodiments, from 20 to 50 weight percents of the dry weight comprisesor is consisted of synthetic polymers. In some embodiments, from 20 to40 weight percents of the dry weight comprises or is consisted ofsynthetic polymers. In some embodiments, from 20 to 30 weight percentsof the dry weight comprises or is consisted of synthetic polymers. Insome embodiments, from 20 to 25 weight percents of the dry weightcomprises or is consisted of synthetic polymers. In some embodiments, atleast 50 weight percents of the synthetic polymers comprises or isconsisted of polyolefins. In some embodiments, at least 60 weightpercents of the synthetic polymers comprises or consists of polyolefins.In some embodiments, at least 70 weight percents of the syntheticpolymers comprises or is consisted of polyolefins. In some embodiments,at least 80 weight percents of the synthetic polymers comprises orconsists of polyolefins. In some embodiments, at least 90 weightpercents of the synthetic polymers is polyolefins.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 25 weight percents of thedry weight of the feedstock is synthetic polymers. In some embodiments,from 25 to 80 weight percents of the dry weight comprise or consist ofsynthetic polymers. In some embodiments, from 25 to 70 weight percentsof the dry weight comprise or consist of synthetic polymers. In someembodiments, from 25 to 60 weight percents of the dry weight comprise orconsist of synthetic polymers. In some embodiments, from 25 to 50 weightpercents of the dry weight comprise or consist of synthetic polymers. Insome embodiments, from 25 to 40 weight percents of the dry weightcomprise or consist of synthetic polymers. In some embodiments, from 25to 30 weight percents of the dry weight comprise or consist of syntheticpolymers. In some embodiments, at least 50 weight percents of thesynthetic polymers is polyolefins. In some embodiments, at least 60weight percents of the synthetic polymers comprise or consist ofpolyolefins. In some embodiments, at least 70 weight percents of thesynthetic polymers comprise or consist of polyolefins. In someembodiments, at least 80 weight percents of the synthetic polymerscomprise or consist of polyolefins. In some embodiments, at least 90weight percents of the synthetic polymers is polyolefins.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 30 weight percents of thedry weight of the feedstock comprise or consist of synthetic polymers.In some embodiments, from 30 to 80 weight percents of the dry weightcomprise or consist of synthetic polymers. In some embodiments, from 30to 70 weight percents of the dry weight comprise or consist of syntheticpolymers. In some embodiments, from 30 to 60 weight percents of the dryweight comprise or consist of synthetic polymers. In some embodiments,from 30 to 50 weight percents of the dry weight comprise or consist ofsynthetic polymers. In some embodiments, from 30 to 40 weight percentsof the dry weight comprise or consist of synthetic polymers. In someembodiments, at least 50 weight percents of the synthetic polymers ispolyolefins. In some embodiments, at least 60 weight percents of thesynthetic polymers comprise or consist of polyolefins. In someembodiments, at least 70 weight percents of the synthetic polymerscomprise or consist of polyolefins. In some embodiments, at least 80weight percents of the synthetic polymers comprise or consist ofpolyolefins. In some embodiments, at least 90 weight percents of thesynthetic polymers is polyolefins.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 40 weight percents of thedry weight of the feedstock is synthetic polymers. In some embodiments,from 40 to 80 weight percents of the dry weight comprise or consist ofsynthetic polymers. In some embodiments, from 40 to 70 weight percentsof the dry weight comprise or consist of synthetic polymers. In someembodiments, from 40 to 60 weight percents of the dry weight comprise orconsist of synthetic polymers. In some embodiments, from 40 to 50 weightpercents of the dry weight comprise or consist of synthetic polymers. Insome embodiments, at least 50 weight percents of the synthetic polymerscomprise or consist of polyolefins. In some embodiments, at least 60weight percents of the synthetic polymers comprise or consist ofpolyolefins. In some embodiments, at least 70 weight percents of thesynthetic polymers comprise or consist of polyolefins. In someembodiments, at least 80 weight percents of the synthetic polymerscomprise or consist of polyolefins. In some embodiments, at least 90weight percents of the synthetic polymers is polyolefins.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 50 weight percents of thedry weight of the feedstock comprise or consist of synthetic polymers.In some embodiments, from 50 to 80 weight percents of the dry weightcomprise or consist of synthetic polymers. In some embodiments, from 50to 70 weight percents of the dry weight comprise or consist of syntheticpolymers. In some embodiments, from 50 to 60 weight percents of the dryweight comprise or consist of synthetic polymers. In some embodiments,at least 50 weight percents of the synthetic polymers comprise orconsist of polyolefins. In some embodiments, at least 60 weight percentsof the synthetic polymers comprise or consist of polyolefins. In someembodiments, at least 70 weight percents of the synthetic polymerscomprise or consist of polyolefins. In some embodiments, at least 80weight percents of the synthetic polymers comprise or consist ofpolyolefins. In some embodiments, at least 90 weight percents of thesynthetic polymers is polyolefins.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, the feedstock contains at least 90weight percents (dry weight) of an organic material other than thermosetpolymers and synthetic polymers having a melting point of at least 250°C. In some embodiments, the feedstock contains at least 95 weightpercents (dry weight) of an organic material other than thermosetpolymers and synthetic polymers having a melting point of at least 250°C. In some embodiments, the feedstock contains at least 98 weightpercents (dry weight) of an organic material other than thermosetpolymers and synthetic polymers having a melting point of at least 250°C. In some embodiments, the feedstock contains at least 99 weightpercents (dry weight) of an organic material other than thermosetpolymers and synthetic polymers having a melting point of at least 250°C.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, the feedstock contains at least 90weight percents (dry weight) of an organic material other than PVC. Insome embodiments, the feedstock contains at least 95 weight percents(dry weight) of an organic material other than PVC. In some embodiments,the feedstock contains at least 98 weight percents (dry weight) of anorganic material other than PVC. In some embodiments, the feedstockcontains at least 99 weight percents (dry weight) of an organic materialother than PVC. In some of any of the embodiments pertaining to a methodof processing waste material as described herein, the feedstock containsat least 90 weight percents (dry weight) of an organic material otherthan PVC, thermoset polymers and synthetic polymers having a meltingpoint of at least 250° C. In some embodiments, feedstock contains atleast 95 weight percents (dry weight) of an organic material other thanPVC, thermoset polymers and synthetic polymers having a melting point ofat least 250° C. In some embodiments, the feedstock contains at least 98weight percents (dry weight) of an organic material other than PVC,thermoset polymers and synthetic polymers having a melting point of atleast 250° C. In some embodiments, the feedstock contains at least 99weight percents (dry weight) of an organic material other than PVC,thermoset polymers and synthetic polymers having a melting point of atleast 250° C.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, no more than 5 weight percents ofthe dry weight of the feedstock is inorganic material. In someembodiments, no more than 4 weight percents is inorganic material. Insome embodiments, no more than 3 weight percents is inorganic material.In some embodiments, no more than 2 weight percents is inorganicmaterial. In some embodiments, no more than 1 weight percent isinorganic material. In some embodiments, no more than 0.5 weight percentis inorganic material. In some embodiments, no more than 0.2 weightpercent is inorganic material. In some embodiments, no more than 0.1weight percent is inorganic material.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, at least 1 weight percent of the dryweight of the feedstock is inorganic salts (e.g., including inorganicsalts derived from an aqueous salt solution used for separationaccording to specific gravity). In some embodiments, at least 1.5 weightpercent of the dry weight of the feedstock is inorganic salts. In someembodiments, at least 2 weight percent of the dry weight of thefeedstock is inorganic salts. In some embodiments, at least 2.5 weightpercent of the dry weight of the feedstock is inorganic salts. In someembodiments, at least 3 weight percent of the dry weight of thefeedstock is inorganic salts.

Without being bound by any particular theory, it is believed thatinorganic salts (e.g., salts derived from an aqueous salt solution usedfor separation according to specific gravity) facilitate processing ofthe feedstock by mixing and heating (e.g., as described herein) to forma processed material with desirable properties.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the feedstock comprising a sortedmaterial as described herein may optionally consist essentially of thesorted material.

Alternatively, in some of any of the embodiments described herein in thecontext of a method of processing waste material, providing thefeedstock as described herein comprises combining the sorted materialwith one or more additional materials. In some embodiments, the methodfurther comprises mixing the sorted material with an additionalmaterial. An additional material may optionally be added to the sortedmaterial in order to fine-tune the composition of the feedstock (e.g.,to arrive at a feedstock composition described herein) and/or to impartthe obtained processed material with a desired property and/or becauseit is desired to process the additional material (e.g., so as to avoidthe need to dispose of it by other means).

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the sorted materialand the additional material are mixed (e.g., the feedstock is provided)prior to subjecting the feedstock to mixing via shear forces asdescribed herein. Thus, the heating and mixing via shear forcesdescribed herein is optionally performed on a previously preparedfeedstock.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the sorted materialand the additional material are mixed concomitantly with subjecting thematerial to mixing via shear forces as described herein, that is,providing the feedstock and subjecting the feedstock to mixing via shearforces are optionally performed concomitantly.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the method further comprises mixingthe processed material with an additional material. In theseembodiments, the additional material can be mixed with a processedmaterial obtained at the end of processing of the feedstock (e.g., uponsubjecting the feedstock to one or numerous cycles of heating and/ormixing), or, during processing of the feedstock (e.g., upon subjectingthe feedstock to a first cycle of heating and/or mixing and prior tosubjecting the feedstock to a second cycle of heating and/or mixing;upon subjecting the feedstock to a first cycle of heating and/or mixingand prior to gas removal; upon subjecting the feedstock to a first cycleof heating and/or mixing, subsequent to gas removal and prior tosubjecting the feedstock to a second cycle of heating and/or mixing; orupon subjecting the feedstock to a first cycle of heating and/or mixingand gas removal and to a second cycle of heating and/or mixing, butprior to a second gas removal).

In embodiments where an additional material is mixed with a processedmaterial, the additional material is supplemented to the container whereprocessing is performed, at a desired section of the container.

In any of the embodiments described herein relating to an additionalmaterial, an additional material added to a sorted material mayoptionally be a material consisting primarily (e.g., more than 50 weightpercents) of water, for example, water or an aqueous solution. Asdescribed herein, addition of water may be used to increase a watercontent of the feedstock.

In any of the embodiments described herein relating to an additionalmaterial, the additional material (other than water) may optionallycomprise animal and/or plant material.

Alternatively or additionally, the additional material (other thanwater) is not derived from plants or animals.

Examples of animal material which may be added (e.g., to the sortedmaterial) include, without limitation, fecal material (e.g., sewagesolids, manure), corpses, animal organs, feathers, hair (e.g., wool),meat, animal fat, dairy products, egg shells, and bones.

Examples of plant material which may be added (e.g., to the sortedmaterial), without limitation, hay, grass clippings, cuttings,trimmings, inedible portions of crops, leaves, sawdust, wood chips,leaves bark, fruit, vegetables, grains, vegetable oil, textiles (e.g.,cotton, linen, hemp, jute) and paper products (e.g., paper, cardboard).

Animal material and/or plant material may optionally be added (e.g., tothe sorted material), for example, in order to dispose of waste, such assewage (e.g., in the form of sewage sludge), agricultural waste (e.g.,sorted agricultural waste), food industry waste, gardening byproductsand/or carpentry byproducts, and/or for recycling paper products (e.g.,as part of a municipal recycling program).

Alternative examples of optional additional materials (i.e., other thananimal or plant material) include, without limitation, minerals (e.g.,sand, dried cement, stone), glasses (including fiberglass), metals, andpolymeric materials (e.g., synthetic polymers in textiles and/orrubbers). Such materials may optionally be added, for example, in orderto recycle industrial waste, waste from construction activities and thelike, and/or in order to modify and/or enhance the physical propertiesof the processed material (e.g., similarly to the inclusion of sand inconcrete). For example, an additional material may be an elasticmaterial (e.g., rubber or another elastomer), a fiber (e.g., a glassfiber, a polymeric fiber) for enhancing mechanical strength, and/or apolymer for modifying the properties of the obtained processed materialby blending with the processed material (e.g., in a form of a polymerblend).

In embodiments, wherein an additional material is substantially aninorganic material (e.g., a minerals, glass and/or metal), theadditional material is preferably added to the obtained process material(e.g., so as to avoid interference of the inorganic material with theprocessing described herein) and/or selected so as to be a form whichdoes not interfere excessively with the processing (e.g., a fine grainedform which does not cause excessive abrasion and/or clogging).

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, an additional materialand/or an amount thereof is selected based on a composition of thesorted material and a desired composition of the feedstock (e.g., afeedstock composition described herein), for example, wherein acomposition of sorted material differs from a desired composition of thefeedstock.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, a waste material to beprocessed (and/or an amount thereof) and an additional material (and/oran amount thereof) are selected so as to be complementary, for example,wherein an expected composition of a sorted material derived from thewaste material is expected to differ from a desired composition of thefeedstock.

For example, in some embodiments, the waste material comprises arelatively high percentage of plant and/or animal material (e.g., in aform of agricultural waste, trimmings, cuttings, leaves, cardboard,sewage sludge and the like), and consequently has less synthetic polymer(e.g., polyolefins) than desired in the feedstock (e.g., in accordancewith a feedstock composition described herein), and the additionalmaterial is selected to comprise a synthetic material, to thereby obtainthe desired feedstock composition (e.g., while also facilitatingrecycling of the aforementioned waste material).

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the additionalmaterial comprises material (e.g., an inorganic material, a polymer)separated from a material (e.g., primarily inorganic material)previously separated from the waste material as described herein, thatis, a portion of the material (e.g., an inorganic material, a polymer)removed from the waste material is returned thereto.

The additional material may optionally be a sorted material obtained bysorting the same waste material (e.g., using a different process) and/ora sorted material obtained by sorting a different waste material.

For example, an additional material may optionally comprise at least aportion of a lignocellulose-rich material removed by precipitation in aliquid having a specific gravity of no more than 1.03, and optionally nomore than 1.01 (e.g., water), in which the sorted material does notsink. The lignocellulose-rich material removed from a waste material, ora residue remaining upon fermentation/anaerobic digestion oflignocellulose, may optionally be added (e.g., returned, if originatingfrom the same waste material) to the sorted material.

In another example, an additional material may optionally comprise apolymeric material obtained by sorting waste material in a liquid havinga specific gravity of no more than 1.03, and optionally no more than1.01 (e.g., water), in which low-density polymers (e.g., polyolefins) donot sink (whereas materials such as lignocellulose, high-densitypolymers and inorganic materials sink). The sorted polymeric materialmay be sorted from the same waste material or a different wastematerial.

Optionally or additionally, the polymeric material is obtained uponsubjecting another waste material to a separation according to specificgravity as described herein.

It is to be appreciated that the additional materials may optionally becomposite materials, such as laminates (e.g., comprising a polymer incombination with a paper product and/or a metal) and glass-polymercomposites (e.g., comprising glass fiber embedded in a polymer). Suchcomposite materials are particularly difficult to recycle by standardmethods.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the additionalmaterial comprises at least one carbohydrate (e.g., a monosaccharide, adisaccharide, a trisaccharide, an oligosaccharide, a polysaccharide).

Without being bound by any particular theory, it is believed thatcarbohydrates react during heating and mixing as described herein in amanner which results in processed material with desirable properties.

The carbohydrate(s) may be from any source described herein (e.g.,animal or plant material).

In some embodiments of any of the embodiments described herein,carbohydrate(s) is obtained from a liquid (e.g., aqueous solution) whichleaches out of the waste material and/or sorted material (e.g., apartially sorted material), for example, upon compression and/ordrainage of the material (e.g., as described herein), prior to providingthe feedstock, and is collected. Such a liquid may leach out of wastematerial during or shortly after a shredding process and/or during aseparation process described herein, for example, a liquid removedsubsequent to a cycle of separating materials according to specificgravity, as described herein (e.g., comprising a carbohydrate in anaqueous salt solution). A carbohydrate(s) obtained from the liquid mayoptionally be used as an additional material described herein.

In some embodiments of any of the embodiments described herein, thecarbohydrate(s) is separated from at least a portion of the liquid fromthe waste material and/or sorted material (e.g., a partially sortedmaterial). In some embodiments, the carbohydrate(s) is concentratedprior to being added to the sorted material, for example, by evaporationand/or filtration of the liquid.

In some embodiments of any of the embodiments described herein, thecarbohydrate(s) obtained from a liquid (as described herein) mayoptionally be used as a feedstock material for a process other than theprocessing of a waste material described herein, for example, forpreparation of a polymeric material (e.g., a polysaccharide-containingand/or polylactic acid-containing material). A carbohydrate(s) obtainedfrom a liquid derived from the waste material and/or sorted material(e.g., a partially sorted material) may be processed by techniques knownin the art, for example, by heat treatment, fermentation, cross-linking,condensation, and/or polymerization.

In some embodiments of any of the embodiments described herein, thecarbohydrate(s) is separated from some or all of the liquid derived fromthe waste material and/or sorted material (e.g., a partially sortedmaterial) prior to further processing, for example, by concentrationand/or purification of the carbohydrate(s) (e.g., as described herein).

In some embodiments of any of the embodiments described herein, thecarbohydrate(s) is processed while in liquid derived from the wastematerial and/or sorted material (e.g., a partially sorted material),that is, without first separating the carbohydrate(s) from the liquid.For example, the liquid may be treated by heating and/or addition of areagent such as a cross-linking agent, an enzyme, a microorganism, anacid, a base, an organic solvent and/or any other reagent used in thechemical arts for effecting fermentation, cross-linking, condensation,and/or polymerization.

In some embodiments of any of the embodiments described herein, thecarbohydrate(s) is processed as described herein so as to produce apolysaccharide-containing polymeric material (e.g., a plastarchmaterial).

In some embodiments of any of the embodiments described herein, thecarbohydrate(s) in the liquid are subjected to fermentation (e.g., by amicroorganism or isolated enzymes), so as to convert the carbohydrate(s)to a metabolite, for example, lactic acid. In some embodiments, themetabolite (e.g., lactic acid) in the liquid is then processed asdescribed herein (e.g., to produce polylactic acid).

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, the feedstock prior to mixing andheating is a shredded feedstock. Feedstock may optionally be obtained ina shredded form (e.g., in a form of a shredded sorted material and/oradditional material as described herein), or the method may optionallyfurther comprise shredding the feedstock prior to the mixing and heatingdescribed herein.

Optionally, the feedstock is substantially devoid of relatively largeparticles. Particles above a certain size may be removed, for example,by sieving.

In some of any of the embodiments pertaining to a method of processingwaste material as described herein, solid particles in the feedstock(e.g., shredded feedstock) are less than 50 mm in diameter, optionallyless than 20 mm in diameter. In some embodiments, the solid particlesare less than 10 mm in diameter. In some embodiments, the solidparticles are less than 5 mm in diameter. In some embodiments, the solidparticles are less than 2 mm in diameter.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the heating of the feedstock is ata temperature of at least 90° C. In some embodiments, the heating of thefeedstock is at a temperature of at least 100° C. In some embodiments,the heating of the feedstock is at a temperature of at least 110° C. Insome embodiments, the heating of the feedstock is at a temperature of atleast 120° C. In some embodiments, the heating of the feedstock is at atemperature of at least 130° C. In some embodiments, the heating of thefeedstock is at a temperature of at least 140° C. In some embodiments,the heating of the feedstock is at a temperature of at least 150° C. Insome embodiments, the heating of the feedstock is at a temperature of atleast 160° C.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the heating of the feedstock is ata temperature of no more than 230° C. In some embodiments, the heatingof the feedstock is at a temperature of no more than 225° C. In someembodiments, the heating of the feedstock is at a temperature of no morethan 210° C. In some embodiments, the heating of the feedstock is at atemperature of no more than 200° C. In some embodiments, the heating ofthe feedstock is at a temperature of no more than 190° C. In someembodiments, the heating of the feedstock is at a temperature of no morethan 180° C.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the heating of the feedstock is ata temperature in a range of from 90° C. to 230° C. In some embodiments,the heating of the feedstock is at a temperature in a range of from 90°C. to 180° C. In some embodiments, the heating of the feedstock is at atemperature in a range of from 140° C. to 180° C. In some embodiments,the heating of the feedstock is at a temperature in a range of from 180°C. to 225° C.

The heating may optionally be at a constant temperature throughout theheating process.

Alternatively, the temperature may vary during the heating process. Forexample, in exemplary embodiments, the heating is at a temperature ofabout 110° C. in one stage of the heating process, and from about 180 toabout 225° C. in a later stage of the heating process, as is furtherdiscussed in detail herein below with regard to repeating cycles ofheating and mixing.

Herein, the term “about”, when used in reference to a temperature,indicates ±10° C. In some embodiments, “about” indicates ±5° C.

Subjecting the feedstock to mixing via shear forces may optionally beperformed prior to, concomitant with, and/or subsequent to subjectingthe feedstock to heating. In exemplary embodiments, subjecting thefeedstock to mixing via shear forces is performed concomitant with thefeedstock to heating.

For simplicity, the step of subjecting the feedstock to mixing via shearforces and the step of subjecting the feedstock to heating (as thesesteps are described herein), are referred to herein as “mixing and/orheating”. Thus, the phrase “mixing and/or heating” refers to heatingwith temperatures described herein and to mixing with shear forces asdescribed herein.

Mixing may be effected by any method which generates shear forces.

As used herein and in the art, “shear force” refers to a force whichcauses a stress in a material in a direction which is parallel to across-section of the material. It is to be appreciated that movement offluids over a solid surface characteristically incurs a shear force.

Hence, according to some of any of the embodiments described herein inthe context of a method of processing waste material, mixing isperformed in such a way as to maximize passage of feedstock over solidsurfaces. Optionally, solid components with large surface areas (e.g., ascrew, a propeller) are utilized to increase shear force.

Optionally, shear forces are generated by a compounder, such as, withoutlimitation, an extruder, an internal mixer (a Banbury® mixer), aco-kneader, and/or a continuous mixer etc.

The shear forces and mixing time should be sufficient such that theobtained processed material is essentially evenly dispersed matterthroughout the mass/body thereof.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the shear forces are characterizedby a shear rate of at least 1 second⁻¹, optionally at least 2 second⁻¹,optionally in a range of from 3 second⁻¹ to 300 second⁻¹. In someembodiments the shear rate is in a range of from 1 to 30 second⁻¹. Insome embodiments the shear rate is in a range of from 30 to 100second⁻¹. In some embodiments the shear rate is in a range of from 100to 200 second⁻¹. In some embodiments the shear rate is in a range offrom 200 to 300 second⁻¹.

According to optional embodiments, mixing is effected by rotation of ascrew. The screw is optionally in a barrel (e.g., the barrel forming aclosed container). The barrel may optionally be heated (e.g., by anelectric heater) in order to effect heating along with mixing.Alternatively or additionally, the screw may optionally be heated (e.g.,by a flow of heated fluid inside the screw) in order to effect heatingalong with mixing.

In some of any of the embodiments described herein in the context of amethod of processing waste material, mixing is effected by rotation of ascrew in an extruder.

An extruder typically comprises a heated barrel containing rotatingtherein a single or multiple screws. When more than a single screw isused, the screws may be co-rotated or counter-rotated. Screws may beintermeshing, or non-intermeshing. The extrusion apparatus may be asingle extruder or combinations of extruders (such as in tandemextrusion) which may be any one of the extruders known in the plasticsindustry, including, without limitation, a single screw extruder, atapered twin extruder, a tapered twin single extruder, a twin screwextruder, a multi-screw extruder. In some embodiments of any of theembodiments described herein relating to an extruder, the extruder is asingle screw extruder.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the extruder is equipped with aventing zone. In some embodiments, the extruder is equipped with morethan one venting zone. In some embodiments the nozzle of the extruder ischilled during the extrusion process.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the method further comprisespassing the material being processed through at least one screen duringthe mixing and/or heating. Optionally, a plurality of screens are used(the screens being the same or different in dimensions), such that thematerial being processed is passed through screens at more than onestage of the heating and/or mixing.

As used herein, the term “screen” encompasses any apparatus havingspaces which selectively allows the passage of solid material withsufficiently small dimensions.

In some embodiments, the spaces in the screen are no more than 10 mm inwidth. In some embodiments, the spaces in the screen are no more than 5mm in width. In exemplary embodiments, the spaces are about 3 mm inwidth.

Without being bound by any particular theory, it is believed that theuse of a screen results in a more homogeneous and non-particulateprocessed material, by removing solid particles containing materialswhich do not considerably melt or soften upon heating, in contrast tothe bulk of the material being processed.

However, the present inventor has found that the use of one or morescreens when processing waste material is limited by the tendency ofscreens to be clogged during processing, for example, by solid materialswhich the screens are intended to remove, and/or by fluids which are tooviscous to readily pass through the screens. Such clogging may requireconsiderably time for cleaning and/or replacing the screens, therebysignificantly reducing efficiency of the processing. The presentinventor has further uncovered that sorting waste material according toa method described herein considerably reduces clogging of screens,thereby facilitating their use.

Without being bound by any particular theory, it is believed thatsorting waste material according to a method described herein reducesclogging by removing materials which remain solid upon heating (e.g.,inorganic materials, thermoset synthetic polymers, synthetic polymershaving a high melting point), and/or by increasing a proportion ofpolymers (e.g., polyolefins) which readily melt upon heating (e.g.,thereby enhancing flow of the material being processed). It is furtherbelieved that the use of feedstock with a relatively high water content(e.g., as described herein) may reduce clogging by decreasing aviscosity of the feedstock.

In some of any of the embodiments described herein in the context of amethod of processing waste material, mixing and/or heating is performedunder conditions with relatively low oxygen concentrations. Low oxygenconcentrations may optionally be obtained by performing the mixingand/or heating in a closed container having a low volume of air.Optionally, the volume of air in the container is less than 30% of thecontainer volume, optionally less than 20% of the container volume,optionally less than 10% of the container volume, optionally less than5% of the container volume, optionally less than 2% of the containervolume, and optionally less than 1% of the container volume.

Optionally, air is removed from a closed container by generating avacuum in the container, in order to lower an oxygen concentration inthe container during mixing and/or heating.

Alternatively or additionally, air is removed from a closed container byflushing the container with a gas which comprises little (e.g., lessthan 20%) or no oxygen (e.g., nitrogen gas, argon gas, carbon dioxide),in order to lower an oxygen concentration in the container during mixingand/or heating.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the feedstock is compressed priorto heating and mixing, thereby lowering the volume of air includedwithin the feedstock itself.

An extruder may optionally be used to compress the feedstock. Forexample, the feedstock may enter a first extruder to be subjected toheating and mixing, while a tandem extruder (e.g., perpendicular to thefirst extruder) compresses the feedstock entering the first extruder inorder to remove air. The tandem extruder may comprise, for example, aconical extruder and/or an internal mixer (e.g., a Banbury® mixer).

Without being bound by any particular theory, it is believed thatexcessive oxidation reactions may adversely affect the utility of theprocessed material, and that performing the disclosed process underconditions with relatively low oxygen concentrations is desirable isorder to reduce the level of such oxidation reactions. For example,excessive oxidation (e.g., combustion) may break down the solidmaterials in feedstock to a considerable extent, thereby weakening theobtained processed material.

It is further believed that some of the reactions which advantageouslyaffect the utility of the processed material are endothermic, in sharpcontrast to exothermic oxidation reactions (e.g., combustion). Anadditional advantage of limiting exothermic oxidation reactions is thatexcessive exothermic reactions may be difficult to control.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the method further comprisesremoving gases released during mixing and/or heating. The gases includesteam (gaseous water), and may further include additional gases, such asvapors of volatile organic compounds.

Optionally, removal of gases is effected using suction, e.g., via apump.

Optionally, the method comprises removing gases (as described herein)more than once (i.e., at more than one stage of the process), forexample, twice, three times, four times, and even more. In exemplaryembodiments, gases are removed twice.

It has been demonstrated that removal of gases during the processaffects the properties of the obtained processed material. For example,removal of steam during the process facilitates a gradual reduction inwater content during processing from the relatively high concentrationfound in the feedstock (e.g., as described herein) to a lowconcentration (e.g., as described herein) which allows for beneficialphysicochemical properties of the processed material. In addition,removal of gases during the process prevents formation of excessivepressure, and thereby allows for a thorough, long-lasting process, whichfurther enhances the physicochemical properties of the processedmaterial.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the processed material obtained bymixing and/or heating (e.g., as described hereinabove) is subjected toat least one additional cycle of mixing and/or heating, as describedherein, so as to obtain at least one additional processed material.Thus, the method may comprise, for example, 2 cycles, 3 cycles, 4cycles, 5 cycles, and even more, of mixing and/or heating as describedherein, wherein each cycle produces a new processed material, until afinal processed material is produced by the final cycle.

In exemplary embodiments, the method comprises two cycles of mixingand/or heating, as described herein. A first processed material obtainedfrom the first cycle of mixing and/or heating is subjected to a secondcycle of mixing and/or heating, thereby producing a second, and final,processed material.

The various cycles of mixing and/or heating may be effected by movingthe material being processed between different zones for mixing and/orheating.

Optionally, each of the cycles of mixing and/or heating furthercomprises removing gases (e.g., as described herein) released during thecycle. Thus, the method may optionally comprise sequential cycles (e.g.,2 cycles), each comprising mixing and/or heating, as described hereinand removing gases, as described herein.

Alternatively, one or more cycles comprise both mixing and/or heatingand removing gases and the other cycles comprise only mixing and/orheating, as described herein.

Optionally, a final cycle of mixing and/or heating does not compriseremoving gases released during the cycle (e.g., wherein little or nogases are released during the final cycle). Thus, the method mayoptionally comprise sequential cycles (e.g., 2 cycles) of mixing and/orheating and removing gases, followed by a final cycle (e.g., a thirdcycle) of mixing and/or heating without removing gases.

Thus, an exemplary process according to some embodiments of the presentinvention is effected by subjecting the feedstock as described herein tomixing and to heating, at certain conditions (e.g., certain mixingtechnology and a certain temperature, as described hereinabove, whichcan be referred to in this context as a first temperature).

In some of any of the embodiments described herein in the context of amethod of processing waste material, upon the mixing and heating, afirst removal of gases is effected, as described herein.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the resultingprocessed material is then subjected to a second cycle of mixing andheating, as described herein, at certain conditions (e.g., certainmixing technology and a certain temperature, as described hereinabove,which can be referred to in this context as a second temperature.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, upon the mixing andheating, a second removal of gases is effected, as described herein.

In some embodiments, the above is repeated for as many cycles asdesired.

Thus, in some embodiments of any of the embodiments described herein inthe context of a method of processing waste material, the processedmaterial resulting from a second cycle of mixing and heating (e.g., asdescribed hereinabove) is then subjected to a third cycle of mixing andheating, as described herein, at certain conditions (e.g., certainmixing technology and a certain temperature, as described hereinabove,which can be referred to in this context as a third temperature).

In each cycle, the conditions for mixing and heating can be the same ordifferent.

In each cycle, the removal of gases can be effected or not.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, mixing is the same ineach of cycles.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the first, second,third, and so on, temperature is different.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the first temperatureis higher than the second temperature.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the first temperatureis lower than the second temperature.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the second temperatureis higher than the third temperature.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the second temperatureis lower than the third temperature.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the first temperatureis higher than the third temperature.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the first temperatureis lower than the third temperature.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the third temperatureis about 150° C.

In an exemplary process, mixing is effected by a screw of an extruder,the first temperature is about 110° C. and the second temperature isfrom about 180 to about 225° C.

In some embodiments of this exemplary process, the first temperature andsecond temperature are achieved by the same heating mechanism, and thedifference between the two temperatures is a result of changes in theproperties of the material being processed (e.g., the lower secondtemperature reflecting an increasingly endothermic reaction).

In this exemplary process, removal of gases is effected within eachcycle.

In an exemplary process, removal of gases is effected by a pump.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the total duration (i.e., includingall cycles) of heating of feedstock is at least 5 minutes. In someembodiments, total duration of heating of feedstock is at least 10minutes. In some embodiments, the total duration of heating of feedstockis at least 15 minutes. In some embodiments, the total duration ofheating of feedstock is at least 20 minutes. In some embodiments, thetotal duration of heating of feedstock is at least 30 minutes. In someembodiments, the total duration of heating of feedstock is at least 40minutes. In some embodiments, the total duration of heating of feedstockis at least 60 minutes.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, upon the first mixingand heating described hereinabove, water in the material being processedis eliminated via removal of steam formed by the heating and/or mixing(e.g., via removal of evaporated water during removal of gases). Inaddition, water may optionally be further eliminated via chemicalreactions (e.g., hydrolysis, in which a water molecule reacts withanother molecule, resulting in cleavage of a covalent bond).Consequently, the water content is reduced during the process.Optionally, mixing and/or heating are performed until the water contentof the material being processed is reduced to a desired level.

Water content may be measured, for example, using a commerciallyavailable moisture gauge.

As the mixing and/or heating process results in evaporation of water,mixing and/heating is optionally performed at a suitable temperature anda suitable length of time which result in sufficient evaporation ofwater. In addition, gas removal is optionally performed at a ratesuitable for eliminating substantially all of the generated water vapor,until the water content of the waste material is reduced to a desiredlevel.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the majority of the water in thefeedstock is eliminated via a first gas removal, such that the watercontent of the processed material obtained after the first gas removalis less than 50% of the water content of the feedstock before effectingthe process. Optionally, any additional gas removals effect a furtherreduction of the water content to a low concentration such as describedherein (e.g., less than 1 weight percent).

In some of any of the embodiments described herein in the context of amethod of processing waste material, the method described herein iseffected such that the obtained processed material has a water contentof less than 1 weight percent. In some embodiments, the water content ofthe processed material is less than 0.1 weight percent.

In some of any of the embodiments described herein in the context of amethod of processing waste material, mixing, heating and removal ofgases are performed until a water content of the processed material isless than 0.03 weight percent. In some embodiments, mixing, heating andremoval of gases are performed until a water content of the processedmaterial is less than 0.01 weight percent. In some embodiments, mixing,heating and removal of gases are performed until a water content of theprocessed material is less than 0.003 weight percent. In someembodiments, mixing, heating and removal of gases are performed until awater content of the processed material is less than 0.001 weightpercent.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the method further comprisescontacting the waste material or sorted waste material (e.g., asdescribed herein) with an acidic substance (e.g., a solid or liquidsubstance comprising an acid), to thereby provide a feedstock that ismore acidic than it would have been in the absence of the contactingwith the acidic substance. In some embodiments, the additionalmaterial(s) added to the sorted material, as described herein, comprisethe acidic substance.

Without being bound by any particular theory, it is believed that acidenhances reactions during the mixing and heating process describedherein, in an advantageous manner.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the acidic solution issufficiently acidic so as to result in cleavage of lignocellulose in thewaste material, sorted material and/or feedstock to smaller units (e.g.,cleavage of polysaccharide to smaller polysaccharide, oligosaccharide,trisaccharide, disaccharide and/or monosaccharide units), prior toand/or during mixing and heating as described herein.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, sorted material and/orfeedstock is contacted with the acidic substance (e.g., an acidicliquid), for example, so as not to wash out the acidic substance duringseparation in a liquid as described herein, which may reduce an amountof acid during mixing and heating and/or deleteriously expose devicesinvolved with separation to an acid.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the acidic substanceis mixed with the waste material prior to sorting.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the waste material,sorted material and/or feedstock is submerged in an acidic liquid, andremoved from the acidic liquid, with a portion of the acidic liquidremaining adhered to the material. In some embodiments, the wastematerial, sorted material and/or feedstock is removed from the liquidusing a screw configured for removing solids from a liquid (e.g., aninclined screw). In some embodiments, the waste material, sortedmaterial and/or feedstock is removed from the liquid by filtration.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the acidic substancecomprises hydrochloric acid.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, the acidic substancecomprises an acidic aqueous solution. In some embodiments, the acidicaqueous solution is characterized by a pH of less than 4. In someembodiments, the acidic aqueous solution is characterized by a pH ofless than 3. In some embodiments, the acidic aqueous solution ischaracterized by a pH of less than 2. In some embodiments, the acidicaqueous solution is characterized by a pH of less than 1. In someembodiments, the acidic aqueous solution is characterized by a pH ofless than 0 (i.e., a negative pH).

As described in the Examples herein, the processed material obtainableby heating and mixing as described herein may be thermoplastic andconsequently moldable.

Herein, “thermoplastic” refers to an ability to undergo a reversibletransition to a deformable state when heated. The deformable state maybe, for example, a liquid which results from melting upon heating, or asoftened solid or semi-solid, which may be readily deformed (as plasticdeformation) by application of pressure.

Herein, the term “moldable” refers to an ability to deform a shape of amaterial (e.g., upon heating of a thermoplastic material) in acontrollable manner, so as to obtain a product with a pre-determinedshape (e.g., upon cooling of a thermoplastic material after molding).

In some of any of the embodiments described herein in the context of amethod of processing waste material, the method further comprisesmolding the processed material. Molding may be according to anytechnique used in the art for molding thermoplastic substances.

In some embodiments, the molding comprises extrusion molding. In someembodiments, the molding comprises injection molding. In someembodiments, the molding comprises rotation molding. In someembodiments, the molding comprises compression molding.

In some embodiments, an additional material, as described herein, ismixed with the processed material prior to or during molding theprocessed material.

In this manner, articles of a defined configuration may be manufactured.For example, flower pots, housing siding, deck materials, flooring,furniture, laminates, pallets, septic tanks and the like can be preparedby molding or otherwise reshaping the processed material.

Molding may optionally be effected by heating the processed material ata temperature of at least 90° C., optionally at least 100° C.,optionally at least 110° C., optionally at least 120° C., optionally atleast 130° C., optionally at least 140° C., optionally at least 150° C.,optionally at least 160° C., optionally at least 170° C., and optionallyat least 180° C.

In some embodiments, molding is effected at a temperature that rangesfrom about 50° C. to about 200° C., or from about 90° C. to about 180°C. Any intermediate value is contemplated.

Such heating may be effected by maintaining the heating used to processthe feedstock, as described hereinabove, and/or by reheating theprocessed material subsequent to processing of the feedstock by heating,and optionally mixing, as described herein.

Using the process described herein results in a processed material asdescribed herein. The composition of the processed material will besimilar to the feedstock composition (e.g., a feedstock compositiondescribed herein) with the water removed, but will typically be somewhatdifferent than the feedstock composition due to chemical reactionsinduced, for example, by the heating and mixing described herein.

According to optional embodiments, the processed material comprises apolymeric material (e.g., a non-particulate polymeric material).

According to another aspect of some embodiments of the invention, thereis provided a processed material which is a polymeric material (e.g.,non-particulate polymeric material) obtainable by any of the processesas described herein. The polymeric material is optionally and preferablya thermoplastic polymeric material.

Herein “polymeric material” refers to a material in which aconcentration of polymers is at least 50 weight percents of thematerial. The polymers may be synthetic polymers or polymers derivedfrom biomass (e.g., plant material and animal material.

Thus, in some of any of the embodiments described herein in the contextof a method of processing waste material and/or a processed material, atleast 50 weight percents of the processed material consists of polymers.In some embodiments, at least 60 weight percents of the processedmaterial consists of polymers. In some embodiments, at least 70 weightpercents of the processed material consists of polymers. In someembodiments, at least 80 weight percents of the processed materialconsists of polymers. In some embodiments, at least 90 weight percentsof the processed material consists of polymers.

The remainder of the processed material may comprise, for example, ash,residual liquids (e.g., water), small organic compounds (e.g., sugars,furfural, amino acids, lipids), and/or small amounts of inorganicmaterials present in the waste material (e.g., metals, sand, stone,glass and/or ceramic, and/or an inorganic salt derived from an aqueousliquid used in separation, as described herein).

In some of any of the embodiments described herein, the polymericmaterial is a thermoplastic material. It is to be understood that thepolymeric material may comprise a variety of polymers, and that it ismeant that the polymeric material as a whole is thermoplastic, and thatthe polymeric material may comprise polymers which are not characterizedas being thermoplastic per se.

Without being bound by any particular theory, it is believed thatpolymers in the processed material obtained according to embodiments ofthe invention are largely responsible for the thermoplastic propertiesof waste material processed as described herein.

The removal of inorganic materials and optional addition of an inorganicsalt as described herein, affect the elemental composition of theobtained processed material, for example, by increasing a percentage ofcarbon, oxygen, nitrogen, hydrogen and/or elements in the salt (e.g.,alkali metals and/or halogens), particularly carbon and hydrogen (e.g.,because oxygen and nitrogen may be depleted due to their presence ininorganic materials and/or organic materials having a relatively highspecific gravity) and/or by decreasing a percentage of other atoms.

Without being bound by any particular theory, it is believed that theobtained elemental composition is associated with desirable propertiesof the processed material.

In some of any of the embodiments described herein in the context of amethod of processing waste material and/or a processed material, aconcentration of carbon in the processed material is at least 55 weightpercents. In some embodiments, the concentration of carbon is at least57.5 weight percents. In some embodiments, the concentration of carbonis at least 60 weight percents. In some embodiments, the concentrationof carbon is at least 62.5 weight percents. In some embodiments, theconcentration of carbon is at least 65 weight percents. In someembodiments, the concentration of carbon is at least 67.5 weightpercents.

In some of any of the embodiments described herein in the context of amethod of processing waste material and/or a processed material, aconcentration of carbon in the processed material is at least 55 weightpercents. In some embodiments, the concentration of carbon is at least57.5 weight percents. In some embodiments, the concentration of carbonis at least 60 weight percents. In some embodiments, the concentrationof carbon is at least 62.5 weight percents. In some embodiments, theconcentration of carbon is at least 65 weight percents. In someembodiments, the concentration of carbon is at least 67.5 weightpercents.

In some of any of the embodiments described herein in the context of amethod of processing waste material and/or a processed material, a totalconcentration of carbon and hydrogen in the processed material is atleast 65 weight percents. In some embodiments, the concentration ofcarbon and hydrogen is at least 67.5 weight percents. In someembodiments, the concentration of carbon and hydrogen is at least 70weight percents. In some embodiments, the concentration of carbon andhydrogen is at least 72.5 weight percents. In some embodiments, theconcentration of carbon and hydrogen is at least 75 weight percents. Insome embodiments, the concentration of carbon and hydrogen is at least77.5 weight percents. In some embodiments, the concentration of carbonand hydrogen is at least 80 weight percents.

In some of any of the embodiments described herein in the context of amethod of processing waste material and/or a processed material, aconcentration of oxygen in the processed material is at least 20 weightpercents. In some embodiments, the concentration of oxygen is at least22 weight percents. In some embodiments, the concentration of oxygen isat least 24 weight percents. In some embodiments, the concentration ofoxygen is at least 26 weight percents. In some embodiments, theconcentration of oxygen is at least 28 weight percents. In someembodiments, the concentration of oxygen is at least 30 weight percents.

In some of any of the embodiments described herein in the context of amethod of processing waste material and/or a processed material, a totalconcentration of carbon and oxygen in the processed material is at least80 weight percents. In some embodiments, the concentration of carbon andoxygen is at least 82 weight percents. In some embodiments, theconcentration of carbon and oxygen is at least 84 weight percents. Insome embodiments, the concentration of carbon and oxygen is at least 86weight percents. In some embodiments, the concentration of carbon andoxygen is at least 88 weight percents. In some embodiments, theconcentration of carbon and oxygen is at least 90 weight percents.

In some of any of the embodiments described herein in the context of amethod of processing waste material and/or a processed material, a totalconcentration of carbon, hydrogen and oxygen in the processed materialis at least 90 weight percents. In some embodiments, the concentrationof carbon, hydrogen and oxygen is at least 92 weight percents. In someembodiments, the concentration of carbon, hydrogen and oxygen is atleast 94 weight percents. In some embodiments, the concentration ofcarbon, hydrogen and oxygen is at least 96 weight percents. In someembodiments, the concentration of carbon, hydrogen and oxygen is atleast 98 weight percents.

In some of any of the embodiments described herein in the context of amethod of processing waste material and/or a processed material, a totalconcentration of carbon, hydrogen, oxygen, nitrogen, alkali metal andhalogen atoms in the processed material is at least 93 weight percents.In some embodiments, the concentration of carbon, hydrogen, oxygen,nitrogen, alkali metal and halogen atoms is at least 94 weight percents.In some embodiments, the concentration carbon, hydrogen, oxygen,nitrogen, alkali metal and halogen atoms is at least 95 weight percents.In some embodiments, the concentration of carbon, hydrogen, oxygen,nitrogen, alkali metal and halogen atoms is at least 96 weight percents.In some embodiments, the concentration of carbon, hydrogen, oxygen,nitrogen, alkali metal and halogen atoms is at least 97 weight percents.In some embodiments, the concentration of carbon, hydrogen, oxygen,nitrogen, alkali metal and halogen atoms is at least 98 weight percents.In some embodiments, the concentration of carbon, hydrogen, oxygen,nitrogen, alkali metal and halogen atoms is at least 99 weight percents.It is to be appreciated that a relatively high total concentration ofcarbon, hydrogen, oxygen, nitrogen, alkali metal and halogen atomsindicates a relatively low concentration of inorganic material otherthan water-soluble inorganic salts (which typically comprise an alkalimetal action and/or a halogen anion).

In some embodiments, non-hydrogen atoms (e.g., any atoms other thanhydrogen) are quantified. This allows the use of elemental analysistechniques which are not effective at detecting hydrogen atoms (e.g., asexemplified herein).

In some of any of the embodiments described herein in the context of amethod of processing waste material and/or a processed material, atleast 95% of the non-hydrogen atoms in the processed material are carbonor oxygen atoms. In some embodiments, at least 96% of the non-hydrogenatoms are carbon or oxygen. In some embodiments, at least 97% of thenon-hydrogen atoms are carbon or oxygen. In some embodiments, at least98% of the non-hydrogen atoms are carbon or oxygen.

In some of any of the embodiments described herein in the context of amethod of processing waste material and/or a processed material, atleast 97% of the non-hydrogen atoms in the processed material arecarbon, oxygen, nitrogen, alkali metal or halogen atoms. In someembodiments, at least 97.5% of the non-hydrogen atoms are carbon,oxygen, nitrogen, alkali metal or halogen atoms. In some embodiments, atleast 98% of the non-hydrogen atoms are carbon, oxygen, nitrogen, alkalimetal or halogen atoms. In some embodiments, at least 98.5% of thenon-hydrogen atoms are carbon, oxygen, nitrogen, alkali metal or halogenatoms. In some embodiments, at least 99% of the non-hydrogen atoms arecarbon, oxygen, nitrogen, alkali metal or halogen atoms. In someembodiments, at least 99.5% of the non-hydrogen atoms are carbon,oxygen, nitrogen, alkali metal or halogen atoms.

It is to be appreciated that when determining percentage of atoms, asopposed to weight percentages, the elements described herein represent aparticularly high percentage, because atoms associated with inorganicmaterials (e.g., silicon, metals) tend to be heavier and atoms such ascarbon, hydrogen and oxygen, and are therefore disproportionatelyrepresented in weight percentages.

In some of any of the embodiments described herein in the context of amethod of processing waste material and/or a processed material, a molarconcentration of alkali metals in the processed material is at least 50%higher than a molar concentration of alkali metals in the dry weight ofthe waste material. In some embodiments, the molar concentration ofalkali metals is at least 100% higher (i.e., two-fold). In someembodiments, the molar concentration of alkali metals is at least 150%higher. In some embodiments, the molar concentration of alkali metals isat least 200% higher. In some embodiments, the molar concentration ofalkali metals is at least 300% higher. In some embodiments, the molarconcentration of alkali metals is at least 400% higher. In someembodiments, the molar concentration of alkali metals is at least 600%higher. In some embodiments, the molar concentration of alkali metals isat least 900% higher (i.e., ten-fold).

In some of any of the embodiments described herein in the context of amethod of processing waste material and/or a processed material, a molarconcentration of halogens in the processed material is at least 50%higher than a molar concentration of halogens in the dry weight of thewaste material. In some embodiments, the molar concentration of halogensis at least 100% higher. In some embodiments, the molar concentration ofhalogens is at least 150% higher. In some embodiments, the molarconcentration of halogens is at least 200% higher. In some embodiments,the molar concentration of halogens is at least 300% higher. In someembodiments, the molar concentration of halogens is at least 400%higher. In some embodiments, the molar concentration of halogens is atleast 600% higher. In some embodiments, the molar concentration ofhalogens is at least 900% higher.

Herein, the phrase “molar concentration” refers to a number (e.g., inmole units) of molecules or atoms (e.g., alkali metal atoms, halogenatoms) per volume.

Herein, a molar concentration in the dry weight of waste material refersto a molar concentration in the waste material when dried (e.g., byevaporation) until substantially dry (e.g., no more than 1 weightpercent water), for example, wherein a water content of the dried wastematerial is substantially the same as the water content of the processmaterial to which it is being compared.

In some of any of the embodiments described herein in the context of amethod of processing waste material and/or a processed material, amelt-flow index (MFI) of the processed material is at least 1 gram per10 minutes at a temperature of 190° C. (the melt-flow index beingdetermined according to ISO 1133 standards). In some embodiments, theMFI is at least 1.5 grams per 10 minutes. In some embodiments, the MFIis at least 2 grams per 10 minutes. In some embodiments, the MFI is atleast 2.5 grams per 10 minutes. In some embodiments, the MFI is at least3 grams per 10 minutes. In some embodiments, the MFI is at least 3.5grams per 10 minutes. In some embodiments, the MFI is at least 4 gramsper 10 minutes. In some embodiments, the MFI is no more than 10 gramsper 10 minutes (e.g., from 1 to 10 grams per 10 minutes). In someembodiments, the MFI is no more than 8 grams per 10 minutes (e.g., from1 to 8 grams per 10 minutes). In some embodiments, the MFI is no morethan 6 grams per 10 minutes (e.g., from 1 to 6 grams per 10 minutes).

Without being bound by any particular theory, it is believed that amelt-flow index of at least 1 gram per 10 minutes is associated with arelatively high polymeric nature of the processed material (e.g., apolymeric material as described herein), particularly a thermoplasticpolymeric nature of the processed material.

It is further believed that thermoplasticity of the processed material(e.g., as indicated by a MFI as described herein) is associated withrelative flowability of the feedstock during processing by heating andmixing, and that such flowability during processing by heating andmixing advantageously allows for the effective use of screens duringprocessing for removing inhomogeneities (e.g., solid material),resulting in a more homogeneous and non-particulate processed material.In contrast, a feedstock with a lower flowability could tend to clog thescreens, thereby preventing the efficient use of screens to furtherenhance homogeneity and reduce particulate levels of the processedmaterial.

In some of any of the embodiments described herein in the context of amethod of processing waste material and/or a processed material is lessbrittle at low temperatures (e.g., less susceptible to cold-cracking),optionally at 10° C., 0° C., −10° C., and/or −20° C., than a materialobtained by processing (unsorted) waste material instead of sortedmaterial, that is, by processing a feedstock comprising the wastematerial instead of sorted material. In some embodiments, the increasedresistance to cold-cracking is characterized by higher impact strength(e.g., Izod impact strength, Charpy impact strength) at a temperature of10° C., 0° C., −10° C., and/or −20° C.

In some of any of the embodiments described herein in the context of amethod of processing waste material and/or a processed material is moreresistant to combustion (e.g., combustion occurs at a highertemperature) than a material obtained by processing (unsorted) wastematerial instead of sorted material, that is, by processing a feedstockcomprising the waste material instead of sorted material.

Without being bound by any particular theory, it is believed thatreduced brittleness at low temperature and/or higher resistance tocombustion are associated with a lower degree of inhomogeneities, forexample, inhomogeneities (e.g., metals, minerals) which induce crackformation (e.g., increased brittleness) and/or which induce temperatureinhomogeneities upon heating that facilitate combustion.

In some of any of the embodiments described herein in the context of amethod of processing waste material, the processed material ischaracterized as being largely soluble in appropriate solvents, forexample, in organic solvents. It is to be appreciated that being soluble“in organic solvents” may refer to dissolution using multiple solvents(e.g., some of the processed material is soluble in one solvent and someis soluble in another solvent), and does not necessarily indicate thatall of the material can be dissolved in a single solvent.

Such solubility is optionally associated with a high amount of polymersand/or a low amount of inorganic materials.

In some embodiments of any of the embodiments described herein in thecontext of a method of processing waste material, at least 90% of theprocessed material is soluble in organic solvents. In some embodiments,at least 95% of the processed material is soluble in organic solvents.In some embodiments, at least 99% of the processed material is solublein organic solvents. In some embodiments, at least 99.9% of theprocessed material is soluble in organic solvents.

It is to be appreciated that low amounts of non-soluble material rendersa processed material more suitable for being combined with variouspolymers (e.g., polyethylene, polypropylene), which may become fragilewhen combined with excess amounts (e.g., more than 5%, more than 8%) ofnon-soluble (e.g., inorganic) materials.

Without being bound by any particular theory, it is believed thatcarbohydrates such as polysaccharides in the feedstock, at least aportion of which originate in waste material, undergo hydrolysis whensubjected to heating and mixing as described herein, resulting in amixture of monosaccharides, disaccharides, trisaccharides and/oroligosaccharides which may comprise, for example, glucose (which may bederived, for example, from cellulose, hemicellulose and/or starch),and/or xylose, mannose, galactose, rhamnose, and/or arabinose (which maybe derived, for example, from hemicellulose). The substantial degree ofhydrolysis is believed to be due to the initial presence of substantialamounts of water in the feedstock (such as described herein). Inaddition, pyrolysis of polysaccharides may also result inmonosaccharides, disaccharides, trisaccharides and/or oligosaccharides.

It is further believed that carbohydrates in the feedstock furtherundergo polymerization and other forms of covalent bond formation (e.g.,by caramelization and/or Maillard type reactions), resulting in theformation of polymeric materials (e.g., carbohydrates and derivativesthereof) which are not present in the feedstock prior to processing. Itis further believed that pyrolysis further alters the structure ofpolymeric materials in the feedstock during processing, thereby furtherforming polymeric materials which are not present in the feedstock priorto processing.

The degree of hydrolysis is believed to gradually decrease as thematerial being processed becomes progressively drier upon heating duringprocessing, whereas the relative degree of other reactions (e.g.,caramelization, pyrolysis) is believed to gradually increase as thematerial being processed becomes progressively drier.

Thus, in some of any of the embodiments described herein in the contextof a method of processing waste material, the processed polymericmaterial comprises polymers other than those present in the feedstockprior to processing. In some embodiments, at least 1 weight percent ofthe polymeric material in the processed material consists of polymersother than those present in the feedstock prior to processing. In someembodiments, at least 5 weight percents of the polymeric materialconsists of polymers other than those present in the feedstock. In someembodiments, at least 10 weight percents of the polymeric materialconsists of polymers other than those present in the feedstock. In someembodiments, at least 20 weight percents of the polymeric materialconsists of polymers other than those present in the feedstock. In someembodiments, at least 50 weight percents of the polymeric materialconsists of polymers other than those present in the feedstock. In someembodiments, at least 75 weight percents of the polymeric materialconsists of polymers other than those present in the feedstock.

According to some embodiments of any of the embodiments describedherein, the processing described herein results in a loss of thestructure which characterizes plant and animal material in the wastematerial. For example, microscopic examination of plant and animalmaterial typically shows structures such as cell walls and fibrousstructures (e.g., collagen fibers), whereas in the processed material,such structures are optionally substantially absent upon microscopicexamination. In some embodiments, osmotic stress induced by a solute(e.g., a salt) in a solution used for separating according to specificgravity (e.g., as described herein) facilitates loss of the structurewhich characterizes plant and animal material, by altering cellstructure (e.g., cell volume). Such osmotic stress may occur duringseparation according to specific gravity and/or after separationaccording to specific gravity (e.g., due to solute remaining in thesorted material).

Without being bound by any particular theory, it is believed that lossof the original structure of plant and/or animal material reduces thebrittleness and enhances the thermoplasticity of the processed material.

In some embodiments of any of the embodiments described herein in thecontext of a processed material, the processed material (e.g., polymericmaterial) described herein is characterized by a density below 1.2gram/cm³. In some embodiments, the density is below 1.15 gram/cm³. Insome embodiments, the density is below 1.1 gram/cm³. In someembodiments, the density is below 1.05 gram/cm³. In some embodiments,the density is below 1.0 gram/cm³.

Without being bound by any particular theory it is believed thatseparation according to specific gravity, as described herein, isparticularly likely to result in a processed material characterized by arelatively low density (e.g., below 1.2 gram/cm³), as compared to othermaterials made by processing waste materials, as high density materialsare separated from the waste material prior to heating and mixing asdescribed herein.

As described herein, the processed material obtained by the processdescribed herein may be useful for a variety of purposes, such as makingplastic products, and thus facilitates the beneficial recycling of thewaste material.

In some embodiments of any of the embodiments described herein, theprocess described herein allows for disposal of a hazardous material(e.g., a toxic compound, a radioactive compound). A feedstock materialcomprising a hazardous material, for example, sorted material which hasbeen mixed with an additional material that comprises a hazardousmaterial (e.g., a toxic sludge) is processed as described herein so asto provide a processed material in the form of a solid matrix, in whichthe hazardous material is embedded. A degree of leaching of thehazardous material from the solid matrix is low, such that the hazardousmaterial is safely contained.

According to optional embodiments, at least 10 weight percents of theprocessed material consists of one or more synthetic polymers, forexample, synthetic polymers present in the waste material prior toprocessing (e.g., plastic products). In some embodiments, at least 15weight percents of the processed material consists of one or moresynthetic polymers. In some embodiments, at least 20 weight percents ofthe processed material consists of one or more synthetic polymers. Insome embodiments, at least 30 weight percents of the processed materialconsists of one or more synthetic polymers.

The processed material (e.g., polymeric material) described herein mayoptionally be initially formed into pellets and the like and storedbefore further processing it into usable articles (e.g., anarticle-of-manufacturing described herein). The further processing mayinclude injection molding, compression molding or other articlefabricating processes. Further processing may also include mixing virginor recycled plastic with the processed material which may be in the formof pellets or in any other suitable form. This mixture can then beformed into usable objects (e.g., an article-of-manufacturing describedherein).

Mixture of various materials (e.g., virgin or recycled plastic) with theprocessed material (e.g., polymeric material) described herein may be inorder to meet desired specifications, e.g., with respect to physicalproperties, cost, etc. For example, an elastic material may be mixedwith the processed material to provide enhanced elasticity, a rigidmaterial may be mixed with the processed material to provide enhancedrigidity, a particularly cheap material may be mixed with the processedmaterial to reduce costs, and so forth.

In some of any of the embodiments described herein, the processedmaterial (e.g., polymeric material) described herein is combined with anadditional polymeric material (e.g., plastic).

The processed material (e.g., polymeric material) described herein, aswell as a material obtained by mixing the processed material with anadditional material (e.g., a plastic), may optionally be furtherprocessed through a variety of industrial processes known in the art, toform a variety of semi-finished or finished products.

According to another aspect of some embodiments of the invention, thereis provided an article-of-manufacturing formed from the processedmaterial (e.g., polymeric material) described herein.

In some embodiments, the article-of-manufacturing is formed by moldingthe processed material (e.g., polymeric material) described herein(e.g., according to a process described herein).

Non-limiting examples include building material, panels, boards,pallets, pots, and many others.

The processed material (e.g., polymeric material) of embodiments of theinvention related to articles of manufacturing may be the sole componentor may be in a combination with one or more additional materials, suchas a polymer, a compatible polymer blend (a stable blend of immisciblepolymers which bind to one another) and/or a miscible polymer blend (ahomogenous blend of miscible polymers). The processed material may becombined with an additional material by adhering to and/or being blendedwith each of the additional material(s). Optionally, the additionalmaterial is a plastic (e.g., a polymer, a compatible polymer blend or amiscible polymer blend described herein).

The additional material may optionally be a sorted material obtained bysorting the waste same waste material (e.g., using a different process)and/or a sorted material obtained by sorting a different waste material.For example, an additional material may optionally be a polymericmaterial obtained by sorting waste material in a liquid having aspecific gravity of no more than 1.03, and optionally no more than 1.01(e.g., water), in which low-density polymers (e.g., polyolefins) do notsink (whereas materials such as lignocellulose, high-density polymersand inorganic materials sink).

In accordance with some embodiments, the article-of-manufacturing mayinclude also laminates adhered to each other, where at least one layercomprises the processed material (e.g., polymeric material) describedherein. Such multi-layer structures may be obtained by lamination,co-calendering, co-compression, co-extrusion or tandem extrusion of twoor more materials (one being the processed material of embodiments ofthe invention) so as to form the multi-layer product.

As the articles-of-manufacturing described herein comprise processedmaterial derived from waste material, and in some embodiments mayconsist essentially of such processed material, they may be convenientlyrecycled by including the article-of-manufacturing as a waste materialwhich is subjected to the process described herein. Thus, thearticles-of-manufacturing described herein are particularly easy torecycle.

According to another aspect of embodiments of the invention, there isprovided a use of a waste material for the production of anarticle-of-manufacturing described herein. The waste material isoptionally processed as described herein, so as to produce a processedmaterial (e.g., polymeric material) described herein. Optionally, theuse further comprises processing the processed material as describedherein (e.g., by molding the material as described herein).

According to another aspect of embodiments of the invention there isprovided a system for sorting a waste material. The system comprises atleast one separator configured for separating materials in wastematerial according to specific gravity (e.g., as described herein), tothereby obtain a sorted material (e.g., a sorted material describedherein), for example, a sorted material enriched in material having aspecific gravity within a pre-selected range (e.g., as describedherein). In some embodiments, sorted material contains at least 90weight percents of a material having a specific gravity within apre-selected range (e.g., as described herein).

Herein, the terms “separator” and “separating chamber”, which areinterchangeably used herein, refer to a device containing a liquidselected such that a portion of the waste material sinks (e.g., a liquidas described herein), thereby being capable of effecting a cycle ofseparation of inputted material into a relatively high-specific gravitymaterial and relatively low-specific gravity material (e.g., asdescribed herein).

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, one or more separator(s) is configured for removingmaterial which sinks in the liquid. The removed material may betransferred, for example, to a bin adapted for receiving removedmaterials (e.g., inorganic materials, thermoset polymers, PET, PTFE,PVC). In some embodiments, the separator(s) is further configured forconveying material which does not sink to another component of thesystem.

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, one or more separator(s) is configured for removingmaterial which floats in the liquid. The removed material may betransferred, for example, to a bin adapted for receiving removedmaterials. In some embodiments, the separator(s) is further configuredfor conveying material which does not float to another component of thesystem.

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, one or more separator(s) is configured for removingmaterial which floats in the liquid and/or material which sinks in theliquid, the configuration of the separator(s) being controllable andreversible.

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the system is configured for sorting a shredded wastematerial (e.g., as described herein), for example, waste materialsubjected to crushing (e.g., by a hammer mill).

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the system further comprises at least one shredderconfigured for shredding the waste material (e.g., as described herein).

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the system is configured such that at least oneseparator and at least one shredder are in operative communication intandem, such that the system is configured for performing at least oneseparation according to specific gravity and at least one shreddingprocess in a desired sequence (e.g., a sequence described herein).

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the system is configured for shredding the wastematerial prior to contacting the waste material with the liquid of aseparator (e.g., as described herein).

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the system is configured for shredding the sortedmaterial subsequent to contacting the waste material with the liquid ofa separator (e.g., as described herein). Such a sorted waste materialmay be a partially sorted waste material, that is, a sorted material forwhich further sorting (e.g., in a separator as described herein) isintended; or a final sorted waste material, that is, a sorted materialfor which no further sorting is intended.

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the system comprises at least two separators, a firstseparator configured for separating materials according to specificgravity as described herein, to thereby obtain a partially sortedmaterial, and at least one additional separator configured forsubjecting the partially sorted material to at least one additionalcycle of separating materials according to specific gravity (e.g., asdescribed herein). In some embodiments, the system further comprises atleast one shredder configured for shredding the partially sorted wastematerial and/or the sorted waste material subsequent to contact withliquid of any one or more of the separators (e.g., to effect a sequenceof separating and shredding described herein).

Different separators in a system may contain the same liquid ordifferent liquids. The liquid of each separator is preferably selectedsuch that a portion of inputted waste material or partially sortedmaterial sinks therein.

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the system comprises at least one plurality ofseparators and/or at least one plurality of shredders configured tooperate in parallel. In such embodiments, the plurality of separatorsand/or plurality of shredders may be configured to perform essentiallythe same operation, which may allow, for example, a greater throughputof material for such an operation.

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the system further comprises a monitor adapted formonitoring a composition and/or specific gravity of the liquid in one ormore separators. In some embodiments, the monitor is configured toadjust a composition and/or specific gravity of the liquid, for example,for maintaining a specific gravity at a predetermined value (e.g.,within a predetermined range). In some embodiments, the monitor isconfigured for controlling entry of water and/or additional substancesuch as a solute (e.g., a salt described herein) into the separatorliquid, to thereby adjust the composition and/or specific gravity of theliquid.

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the system comprises at least one apparatus (e.g., anoil-water separator described herein) configured for separating oilsfrom a liquid of one or more separators, and optionally collecting oils.Such an apparatus may be configured to remove oils from a separator(e.g., by skimming) and/or from liquid processed outside a separator(e.g., liquid separated from the sorted material outside of a separator,according to any of the respective embodiments described herein).

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the system further comprises an apparatus configuredfor separating at least a portion of liquid from a sorted material bycompression. In some embodiments, the apparatus comprises a screw press.The liquid being separated may comprise, for example, a combination ofliquid used for separating according to specific gravity (according toany of the respective embodiments described herein) and liquid derivedfrom the source waste material (e.g., aqueous liquids and oils).

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, an apparatus configured for separating liquids from asorted material by compression is configured to receive material from atleast one shredder described herein. In some embodiments, the apparatuscomprises a screw press.

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the system comprises at least one reservoir forcollecting carbohydrate-containing and/or oil-containing liquid derivedfrom the waste material, the reservoir being in operative communicationwith at least one component of the system which handles waste materialand/or a material derived therefrom. In some embodiments, the reservoiris in communication with at least one shredder adapted for conveyingliquid from waste material and/or a sorted material derived therefromundergoing shredding to the reservoir (e.g., being adapted for drainingliquid).

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the reservoir is configured for separating oils fromat least a portion of the liquid (e.g., as described herein).

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the reservoir is configured for separatingcarbohydrate(s) from at least a portion of the liquid (e.g., asdescribed herein).

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the reservoir is configured as a fermentor and/orreactor suitable for processing the carbohydrate(s) by fermentation,heating, and/or reaction with a reagent (e.g., as described herein).

FIG. 3 is a schematic illustration of a system 130 for processing wastematerial, according to some embodiments of the present invention. System130 optionally and preferably comprises one or more separating chambers132 for removing at least a portion of inorganic materials in the wastematerial and an extruder system, such as, but not limited to, extrudersystem 110.

In some embodiments, one or more of the separating chambers removesmaterial (e.g., inorganic materials, thermoset polymers, PET, PTFE, PVC)which sinks in the liquid and in some embodiments, one or more of theseparating chambers removes material which floats on the liquid. Alsocontemplated are embodiments in which one or more of the separatingchambers removes material which floats on the liquid and/or materialwhich sinks in the liquid, wherein the configuration of the respectiveseparating chamber is being controllable and reversible. The removedmaterial may be transferred, for example, to a bin (not shown) adaptedfor receiving removed materials.

In some embodiments, system 130 comprises two or more separatingchambers, a first separating chamber for separating materials accordingto specific gravity as described herein, to thereby obtain a partiallysorted material, and at least one additional separating chamber forsubjecting the partially sorted material to at least one additionalcycle of separating materials according to specific gravity (e.g., asdescribed herein).

Different separators in system 130 may contain the same liquid ordifferent liquids. The liquid of each separating chamber is preferablyselected such that a portion of inputted waste material or partiallysorted material sinks therein.

Separating chamber 132 preferably provides the feedstock to extrudersystem either directly or, as illustrated in FIG. 3, via a conduit 134,which is optionally and preferably provided with a controllable valve134′ for controlling the flow from chamber 132 to extruder system 110.The principles according to which the feedstock is formed from the wastematerial are described in greater detail below. In the illustration ofFIG. 3, chamber 132 provides the feedstock to conduit 134 (or directlyto extruder system 110) from the upper part of chamber 132. Thisembodiment is particularly useful when the inorganic material sinks inthe liquid. When the removed inorganic material floats on the liquid, itmay be preferred to constitute chamber 132 to provide the feedstock fromthe lower part of chamber 132.

In some embodiments, system 130 comprises a shredder 138 for shreddingthe material before entering the separation chamber 132 or after exitingseparation chamber 132. While FIG. 3 illustrates a configuration inwhich shredder 138 feeds a shredded waste material to chamber 132 (via aconduit 140, which is optionally and preferably provided with acontrollable valve 140′ for controlling the outflow from shredder 138),this need not necessarily be the case, since in some embodimentsshredder 138 is positioned between chamber 132 and extruder system 110,so that shredder 138 receives the feedstock from chamber 132, shreds thefeedstock and provides a shredded feedstock to extruder system 110(e.g., conduit 140 and valve 140′ which in this embodiment connectshredder 138 with extruder system 110). Further, the present embodimentsalso contemplate configurations in which system 130 comprises more thanone shredder, for example, one shredder before chamber 132 and oneshredder between chamber 132 and extruder system 110.

Thus, the system optionally and preferably is adapted for processing ashredded feedstock (e.g., as described herein). Shredding of feedstockmay be performed by providing the feedstock and then shredding it,and/or by shredding one or more materials (e.g., a sorted material andadditional material(s) described herein) prior to the materials beingcombined to form the feedstock.

In some embodiments, the system comprises two or more shreddersconfigured to operate in tandem, so as to facilitate provision of acontinuous supply of shredded feedstock to extruder system 110.

In some embodiments, system 130 mixes a sorted material (e.g., a sortedmaterial described herein) and or a processed material produced by thesystem an additional material (e.g., as described herein). In someembodiments, system 130 directly mixes the sorted material with anadditional material, to thereby provide the feedstock. In someembodiments, system 130 indirectly mixes sorted material with anadditional material, by mixing waste material with an additionalmaterial prior to sorting the waste material, such that the obtainedsorted material comprises the additional material.

Optionally, the sorted material can be mixed with the additionalmaterial (e.g., prior to the transfer to extruder system 110) using anydevice suitable for mixing such materials.

Alternatively or additionally, extruder system 110 mixes the sortedmaterial with an additional material after the materials are received bysystem 110, such that the feedstock is provided within the barrel of theextruder system.

The various materials employed by system 130 can be provided in separatereservoirs 142. Six reservoirs 142 a-f are shown in FIG. 3 but anynumber of reservoirs is contemplated, including a single reservoir. Eachreservoir optionally and preferably contains a different type ofmaterial. For example, the system may comprise a first reservoir forcontaining a sorted material (e.g., as described herein) and one or morereservoirs for containing one or more additional materials as describedherein and/or a different sorted material than is contained in theaforementioned first reservoir (e.g., sorted material derived from adifferent source of waste material and/or sorted material provided by adifferent sorting process).

Each of the reservoirs is arranged to receive material from shredder 138or chamber 132 or extruder system 110, and/or to feed material intoshredder 138 or chamber 132 or extruder system 110. Material flow fromand/or to the reservoirs is by means of one or more conduits that areschematically illustrated at 144 a-144 f. Other connections are alsocontemplated. One or more of the conduits is optionally and preferablyprovided with a controllable valve for controlling the inflow and/oroutflow from the respective reservoir. These controllable valves areshown at 144 a′-144 f′.

In some embodiments, at least one of reservoirs 142 containscarbohydrate(s) obtained from a liquid derived from the waste material(e.g., as described herein). Such a reservoir is optionally configuredto receive the carbohydrate(s) obtained as described herein.

Controller 123 can also be employed by system 130. The controller isoptionally and preferably configured to control the various valves so asto select the proportions of material from the different reservoirs thatare used for preparing the feedstock. Alternatively, system 130 caninclude more than one controller, wherein one controller (e.g.,controller 123) controls the controllable components of extruder system110, and another controller controls the material proportions. Thecontroller can also include a circuit having monitoring capabilities,for example, for monitoring a composition and/or specific gravity of theliquid the separating chamber, for example, by receiving signals from asensor or a camera 137 installed in or in proximity to separatingchamber 132. In some embodiments, the controller adjusts a compositionand/or specific gravity of the liquid, for example, for maintaining aspecific gravity at a predetermined value (e.g., within a predeterminedrange). In some embodiments, the controller controls the entry of waterand/or additional substance such as a solute (e.g., a salt describedherein) into the separating chamber, to thereby adjust the compositionand/or specific gravity of the liquid.

System 130 optionally and preferably produces a processed materialcomprising a polymeric material (e.g., a processed material describedherein), optionally a thermoplastic polymeric material such as describedherein.

According to another aspect of embodiments of the invention there isprovided a system for processing a waste material (e.g., a wastematerial described herein), to form a non-particulate processed material(e.g., as described herein), wherein a feedstock (e.g., as describedherein) derived from a waste material is subjected to mixing and heatingwithout being dried (e.g., according to a method described herein). Thefeedstock may optionally have a relatively high water content (e.g., asdescribed herein).

The system for processing a waste material incorporates a system forsorting a waste material, comprising one or more separators, asdescribed herein. In some embodiments of any of the embodimentspertaining to a system described herein, the system for sorting a wastematerial is configured for removing at last a portion of inorganicmaterials in the waste material, such that the obtained sorted materialcontains at least 90 weight percents of an organic material (e.g., asdescribed herein).

The system for processing a waste material is configured for providing afeedstock comprising sorted material obtained from the system forsorting a waste material (e.g., a feedstock described herein), thefeedstock having a water content of at least 15 weight percents (e.g., awater content described herein).

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the system is adapted for removing some materials(e.g., inorganic materials, thermoset polymers, PET, PTFE, PVC) fromwaste material (e.g., as described herein), such that the feedstock hasa reduced content of such materials (relative to the waste material).

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the system is configured for contacting the feedstockand/or a material incorporated into the feedstock (e.g., a sortedmaterial and/or a waste material prior to sorting) with an acidicsubstance.

The system for processing a waste material further comprises anapparatus for subjecting the feedstock to mixing via shear forces, andto heating.

FIG. 4 illustrates an exemplary apparatus 200 for subjecting thefeedstock to mixing via shear forces (e.g., as described herein), aswell as optional components of a system for processing a waste materialwhich are associated with the apparatus, according to some embodimentsof the invention. Apparatus 200 comprises an inlet 210 and an outlet260, as well as a first mixing zone 220 and a second mixing zone 240,and optionally a third mixing zone 290, each mixing zone beingindependently adapted for subjecting the feedstock to heating. Apparatus200 further comprises a first vent 230 and a second vent 250, each beingadapted for removing gases released during mixing and heating (e.g., asdescribed herein) from apparatus 200. Apparatus 200 is configured forsubjecting the feedstock entering inlet 210 to mixing in first mixingzone 220, removal of gases released in first mixing zone 220 via firstvent 230, and subsequently subjecting the feedstock to mixing in secondmixing zone 240 and removal of gases released in second mixing zone 240via second vent 250. Apparatus 200 is optionally further configured forsubjecting the feedstock to mixing in third mixing zone 290. Firstmixing zone 220 is adapted for mixing wet feedstock (e.g., wastematerial having a water content described herein), whereas second mixingzone 240 is adapted for mixing semi-wet feedstock (e.g. feedstockpartially dried by heating in mixing zone 220), and optional thirdmixing zone 290 is adapted for mixing dry feedstock (e.g. feedstockdried by heating in mixing zone 240). A processed material then exitsoutlet 260.

In some embodiments, the system further comprises optional apparatus295, which is configured for molding processed material received fromsecond mixing zone 240 or third mixing zone 290. Apparatus 295 mayoptionally be configured as a component of apparatus 200 (e.g., asdepicted in FIG. 4), or alternatively, as a separate apparatus, forexample a separate apparatus which is in communication with apparatus200. Optionally, apparatus 295 is configured for extrusion molding, andcomprises a die suitable for extrusion molding in communication withmixing zone 240 or 290.

In some embodiments, mixing is effected by at least one optional screwand/or blade 270 (e.g., as described herein). The at least one screwand/or blade optionally extents through mixing zones 220 and 240 (andoptionally also mixing zone 290), so as to be capable of effectingmixing in both zones. When more than a single screw and/or blade isused, the screws and/or blades may be co-rotated or counter-rotated. Insome embodiments, mixing zone 220 comprises counter-rotated screwsand/or blades. In some embodiments, mixing zone 240 comprises a singlescrew and/or blade (e.g., configured as an extruder). Screws and/orblades may be intermeshing, or non-intermeshing. In some embodiments,the direction of extrusion through mixing zone 220 is approximatelyperpendicular to the direction of extrusion through mixing zone 240,and/or the direction of extrusion through mixing zone 240 isapproximately perpendicular to the direction of extrusion through mixingzone 290.

Mixing zones 220, 240 and 290 are preferably adapted for subjectingfeedstock to a first cycle, a second cycle, and a third cycle,respectively, of heating and mixing, as described herein. Mixing zones220, 240 and 290 are each independently adapted for heating thefeedstock at a temperature described herein, optionally a temperature ina range of from 90° C. to 230° C., optionally from 90° C. to 180° C.,and optionally from 140° C. to 180° C. Optionally, the apparatus ingeneral, and the mixing zones in particular, are adapted for effectingmixing and heating (e.g., mixing and heating as described herein)simultaneously.

In some embodiments, apparatus 200 is configured such that materialtherein is passed through one or more optional screens (e.g., one ormore screens as described herein). The one or more screens areoptionally configured so as to be readily removable from the apparatus,for example, to facilitate cleaning of the screen(s). The screen(s) mayoptionally be located at any portion of the apparatus, including, forexample, at inlet 210, at outlet 260, in first mixing zone 220, secondmixing zone 240, third mixing zone 290, first vent 230 and/or secondvent 250. In some embodiments, at least one screen is positioned suchthat material passes through the screen(s) shortly before enteringapparatus 295, for example, positioned at the entry into apparatus 295(e.g., when apparatus 295 is configured as a component of apparatus 200)or at outlet 260 (e.g., when apparatus 295 is configured as a separateapparatus, in communication with apparatus 200).

The system optionally comprises at least one temperature control element280 adapted for heating the feedstock as described herein in mixingzones 220 and 240 (and optionally also mixing zone 290). Temperaturecontrol element 280 comprises a heating element (e.g., an electricheater) for heating the waste material, and optionally also a coolingelement (e.g., comprising a cooling fluid) for avoiding excessivetemperatures. A heating element and cooling element may be joined in asingle module, or may be present in separate modules. The system mayoptionally comprise one or more temperature control elements adapted foreffecting heating (and optionally also cooling) in both mixing zones 220and 240, and optionally also mixing zone 290 (as depicted in FIG. 4).Alternatively or additionally, the system comprises separate temperaturecontrol elements for each of mixing zones 220 and 240 (and optionallyalso 290). Alternatively, the system comprises one or more temperaturecontrol elements adapted for effecting heating (and optionally alsocooling) in one mixing zone (e.g., mixing zone 220) directly, whereinheating of the other mixing zone (e.g., mixing zones 240 and/or 290) iseffected by heat transfer from the directly heated mixing zone.

In some embodiments, at least a portion of temperature control element280 is in screw and/or blade 270. Optionally, temperature controlelement 280 comprises a heated (and/or cooled) fluid flowing through atleast a portion of the length of screw and/or blade 270, for effectingheating (and/or cooling), and optionally further comprises a mechanism(which may be inside or outside in screw and/or blade 270) for heating(and/or cooling) the fluid.

In some embodiments, the apparatus further comprises a zone configuredfor intake of the feedstock, being in communication with first mixingzone 220 (e.g., via inlet 210).

In some embodiments, the system further comprises a module configured toallow continuous feeding of feedstock into apparatus 200 (e.g., viainlet 210), such that little or no air enters apparatus 200 with thefeedstock. Such a module may optionally comprise a conical extruderand/or an internal mixer. The module optionally comprises a feedingcontroller configured to monitor (e.g., by weighing) and control a rateof feeding of feedstock into apparatus 200.

In some embodiments, the apparatus further comprises one or more heatingcontrollers for maintaining a desired temperature (e.g., a temperaturedescribed herein) in at least a portion of the apparatus (e.g., in firstmixing zone 220 and/or in second mixing zone 240).

In some embodiments, the apparatus further comprises at least onesensor, for determining a water content of the feedstock at one or morelocations in the apparatus. By monitoring water content, the sensor(s)may allow for control over the water content of the processed materialproduced by the system, such that the processed material will have adesired water content (e.g., a water content described herein), forexample, less than 1 weight percent.

In some embodiments, apparatus 200 is an extruder, as described herein.

In some embodiments, the system is adapted for processing a shreddedfeedstock (e.g., as described herein).

Thus, in some embodiments, the system further comprises a shredderconfigured for shredding feedstock prior to subjecting to mixing (e.g.,prior to intake via inlet 210). In some embodiments, the system isconfigured such that feedstock shredded by the shredder passes into theabovementioned module configured to allow continuous feeding offeedstock into apparatus 200. Shredding of feedstock may be performed byproviding the feedstock and then shredding it, and/or by shredding oneor more materials (e.g., a sorted material and additional material(s)described herein) prior to the materials being combined to form thefeedstock.

In some embodiments, the system comprises at least two shreddersconfigured to operate in tandem, so as to facilitate provision of acontinuous supply of shredded feedstock to inlet 210 (optionally via theabovementioned module configured to allow continuous feeding offeedstock into apparatus 200).

In some embodiments, the system is configured for mixing a sortedmaterial (e.g., a sorted material described herein) and or a processedmaterial produced by the system an additional material (e.g., asdescribed herein).

In some embodiments, the system is configured for directly mixing sortedmaterial with an additional material, to thereby provide the feedstock.In some embodiments, the system is configured for indirectly mixingsorted material with an additional material, by mixing waste materialwith an additional material prior to sorting the waste material, suchthat the obtained sorted material comprises the additional material.

Optionally, the system further comprises an apparatus for mixing thesorted material with the additional material prior to subjecting tomixing in first mixing zone 220 (e.g., prior to intake via inlet 210).Any device used in the art for mixing such materials may be included inthe system.

Alternatively or additionally, the system is configured such that thesorted material is mixed with an additional material in first mixingzone 220, such that the feedstock is provided (in its final form) infirst mixing zone 220 concomitantly with performance of the mixing infirst mixing zone 220.

Without being bound by any particular theory, it is believed that theinclusion of vents 230 and 250 allows for release of excess gases,thereby avoiding potentially damaging increases of pressure inside theapparatus, while maintaining a sufficiently closed system which resultsin a suitable environment (e.g., low oxygen concentration, hightemperature) which facilitates the desired chemical reactions. Inaddition, it is to be appreciated that release of gases removes heat,and may be used to control the temperature in the mixing zones.

It is to be understood, that additional vents and/or additional mixingzones (e.g., between the mixing zones 220 and 240) may be included inthe system.

In some embodiments, the length of the apparatus, as measured frommixing zone 220 to vent 250, is at least 6 meters, optionally at least 7meters, optionally at least 8 meters, optionally at least 9 meters,optionally at least 10 meters, optionally at least 11 meters, optionallyat least 12 meters, and optionally at least 15 meters. In exemplaryembodiments, the length is about 11 meters.

Without being bound by any particular theory, it is believed that theaforementioned lengths allow for a longer residence time of thefeedstock in the apparatus, which enhances the chemical reactions whichoccur therein, thereby improving the physicochemical properties of theobtained processed material.

In some embodiments of any of the embodiments pertaining to an apparatusdescribed herein, the residence time of feedstock in the apparatus is atleast 5 minutes. In some embodiments, the residence time of feedstock inthe apparatus is at least 10 minutes. In some embodiments, the residencetime of feedstock in the apparatus is at least 15 minutes. In someembodiments, the residence time of feedstock in the apparatus is atleast 20 minutes. In some embodiments, the residence time of feedstockin the apparatus is at least 30 minutes. In some embodiments, theresidence time feedstock in the apparatus is at least 40 minutes. Insome embodiments, the residence time of feedstock in the apparatus is atleast 60 minutes.

It is to be noted that the residence time as described hereincorresponds to the duration of the feedstock mixing stage in a method asdescribed herein for processing a waste material.

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, the system further comprises a plurality ofreservoirs, each reservoir being for containing a different type ofmaterial. For example, the system may comprise a first reservoir forcontaining a sorted material (e.g., as described herein) and one or morereservoirs for containing one or more additional materials describedherein and/or a different sorted material than is contained in theaforementioned first reservoir (e.g., sorted material derived from adifferent source of waste material and/or sorted material provided by adifferent sorting process).

The reservoirs are optionally in communication with an apparatus formixing sorted material with the additional material (e.g., as describedherein) and/or for mixing and heating feedstock (e.g., first mixing zone220 in apparatus 200), so as to allow thorough mixing of the materialsfrom the different reservoirs, to thereby form the feedstock.

In some embodiments of any of the embodiments pertaining to a systemdescribed herein, at least one reservoir is for containingcarbohydrate(s) obtained from a liquid derived from the waste material(e.g., as described herein). Such a reservoir is optionally configuredto receive the carbohydrate(s) from an apparatus configured forcollecting the carbohydrate(s) obtained from a waste material-derivedliquid (e.g., as described herein) obtained from one or more componentsof the system, such as one or more shredders and/or one or moreseparators (e.g., as described herein).

Thus, the system optionally further comprises an apparatus configuredfor collecting the carbohydrate(s) from a liquid obtained from one ormore components of the system, such as one or more shredders and/or oneor more separators (e.g., as described herein). Such components incommunication with the apparatus for collecting liquid may optionally beconfigured for conveying waste material-derived liquid to the apparatus.

The system is optionally configured so as to allow control over theproportions of material from the different reservoirs, so as to therebyprovide control over the composition of the feedstock subjected toheating and mixing (e.g., in apparatus 200).

As exemplified in the Examples section, the system described herein issuitable for producing a processed material comprising a polymericmaterial (e.g., a processed material described herein), optionally athermoplastic polymeric material such as described herein.

As used herein the term “about” refers to ±10%.

The terms “comprises”, “comprising”, “includes”, “including”, “having”and their conjugates mean “including but not limited to”.

The term “consisting essentially of” means that the composition, methodor structure may include additional ingredients, steps and/or parts, butonly if the additional ingredients, steps and/or parts do not materiallyalter the basic and novel characteristics of the claimed composition,method or structure.

The word “exemplary” is used herein to mean “serving as an example,instance or illustration”. Any embodiment described as “exemplary” isnot necessarily to be construed as preferred or advantageous over otherembodiments and/or to exclude the incorporation of features from otherembodiments.

The word “optionally” is used herein to mean “is provided in someembodiments and not provided in other embodiments”. Any particularembodiment of the invention may include a plurality of “optional”features unless such features conflict.

As used herein, the singular form “a”, “an” and “the” include pluralreferences unless the context clearly dictates otherwise. For example,the term “a compound” or “at least one compound” may include a pluralityof compounds, including mixtures thereof.

Throughout this application, various embodiments of this invention maybe presented in a range format. It should be understood that thedescription in range format is merely for convenience and brevity andshould not be construed as an inflexible limitation on the scope of theinvention. Accordingly, the description of a range should be consideredto have specifically disclosed all the possible subranges as well asindividual numerical values within that range. For example, descriptionof a range such as from 1 to 6 should be considered to have specificallydisclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from2 to 4, from 2 to 6, from 3 to 6 etc., as well as individual numberswithin that range, for example, 1, 2, 3, 4, 5, and 6. This appliesregardless of the breadth of the range.

Whenever a numerical range is indicated herein, it is meant to includeany cited numeral (fractional or integral) within the indicated range.The phrases “ranging/ranges between” a first indicate number and asecond indicate number and “ranging/ranges from” a first indicate number“to” a second indicate number are used herein interchangeably and aremeant to include the first and second indicated numbers and all thefractional and integral numerals therebetween.

As used herein the term “method” refers to manners, means, techniquesand procedures for accomplishing a given task including, but not limitedto, those manners, means, techniques and procedures either known to, orreadily developed from known manners, means, techniques and proceduresby practitioners of the chemical arts.

It is appreciated that certain features of the invention, which are, forclarity, described in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures of the invention, which are, for brevity, described in thecontext of a single embodiment, may also be provided separately or inany suitable subcombination or as suitable in any other describedembodiment of the invention. Certain features described in the contextof various embodiments are not to be considered essential features ofthose embodiments, unless the embodiment is inoperative without thoseelements.

Various embodiments and aspects of the present invention as delineatedhereinabove and as claimed in the claims section below find experimentalsupport in the following examples.

EXAMPLES

Reference is now made to the following examples, which together with theabove descriptions illustrate some embodiments of the invention in anon-limiting fashion.

Example 1 General Procedure for Separating Waste Material

A general procedure for separating waste material according to someembodiments of the present invention is shown in FIG. 1.

In some embodiments, the procedure is performed using a system such asdescribed and exemplified in FIG. 11 and/or in FIG. 12.

Waste material 10 is provided, optionally “wet” waste material, i.e.,waste material which has not been subjected to drying, and optionallywet substantially unsorted waste material (SUW). The waste material ispreferably domestic waste material, e.g., collected from privatehouseholds. Optionally, the waste material has been subjected topreliminary processing procedures (e.g., at a waste disposal facility),such as crushing (e.g., by a hammer mill), and/or removal of magneticmaterials.

Waste material 10 is subjected to separation according to specificgravity 20 (by contacting the waste material 10 with a liquid),resulting in separation of waste material 10 into a low-specific gravitymaterial 12 and a high-specific gravity material 14. Low-specificgravity material 12 (and optionally high-specific gravity material 14)is subjected to shredding 25, resulting in a shredded material, whichmay optionally be subjected to one or more additional cycles ofseparation of waste material 10 into a low-specific gravity material 12and a high-specific gravity material 14, and optionally shredding thelow-specific gravity material 12 and/or high-specific gravity material14.

The separated high-specific gravity material 14 may optionally befurther sorted so as to extract useful and/or valuable materials such asmetals (e.g., iron, gold) and silica and/or glass (e.g., for use asfiller).

Additional cycles of separation 20 may be according to the samedistinction between low-specific gravity material and high-specificgravity material (e.g., using the same specific gravity of liquid usedfor separation) as in a previous cycle or a different distinctionbetween low-specific gravity material and high-specific gravity material(e.g., using a different specific gravity of liquid used forseparation).

Additional cycles of separation 20 and shredding 25 optionally comprisefiner shredding of material than in a previous cycle.

Optionally, the first cycle of separation 20 and shredding 25 comprisesremoving high-specific gravity inorganic materials which may interferewith shredding 25, followed by at least one additional cycle ofseparation 20.

Optionally, additional cycle of separation 20 is made more effective dueto the previous shredding 25, which facilitates, for example, removal ofair pockets from the material and/or dismantling of waste materialparticles into their component materials.

Optionally, shredding 25 is performed in such a manner as to removeliquid (e.g. liquid absorbed during separation 20) from the sortedmaterial being shredded, for example, by compression (e.g., using ascrew press) and/or drainage of the material during shredding.Optionally, shredding 25 is performed in such a manner after each cycleof separation 20.

Additional materials (e.g., as described herein) may optionally be addedat any stage, during one or more cycles described herein, for example,to waste material 10, to low-specific gravity material 12 and/or tohigh-specific gravity material 14 prior to and/or subsequent toshredding 25.

Sorted material obtained according to this general procedure mayoptionally be subjected to a procedure for processing a feedstock bymixing and heating, e.g., the procedure described in Example 2.

Example 2 General Procedure for Processing a Feedstock Derived fromWaste Material by Mixing and Heating

A general procedure for processing a feedstock derived from wastematerial according to some embodiments of the present invention is shownin FIG. 2.

In some embodiments, the procedure is performed in a system such asdescribed and exemplified in FIG. 4 and/or in FIG. 12.

Sorted material 70 is provided by separating waste material according tothe general procedure described in Example 1, so as to remove at least aportion of inorganic material from the waste material.

The sorted material is optionally combined with an additional material80 to form feedstock 90. Alternatively, feedstock 90 consistsessentially of sorted material 70.

Feedstock 90 comprising the (optionally shredded) sorted material,optionally in combination with an additional material, is subjected tomixing via shear forces 30 and heating 32. In some embodiments, mixing30 and heating 32 are effected in a first zone 220 of apparatus 200shown in FIG. 4. Following mixing 30 and heating 32 is removing 40 ofgases released during said mixing and heating. Removing 40 of the gasesis optionally effected by pumping gases out of the waste material. Insome embodiments, removing of gases 40 is effected in vent 230 ofapparatus 200 shown in FIG. 4.

Mixing 30 and heating 32 and removing 40 result in processed material50. Processed material 50 is then optionally subjected to one or moreadditional cycle 35 of steps 30, 32 and 40. Additional cycle 35 maycomprise the same conditions as steps 30 and/or 32 or differentconditions (e.g., different temperature and or level of shear forces).Processed material 50 may be subjected to molding 60. In someembodiments, molding 60 comprises pelletizing.

In some embodiments, a second cycle of mixing 30 and heating 32 areeffected in a second zone 240 of apparatus 200 shown in FIG. 4. In someembodiments, a second removing of gases 40 is thereafter effected invent 250 of apparatus 200 shown in FIG. 4.

The processed material then optionally undergoes quality control and/orpackaging. In some embodiments, quality control is performed onprocessed material 50 immediately upon completing steps 30, 32 and 40(e.g., while material is still hot). Such quality control is optionallyutilized to regulate any of the previous steps.

Example 3 Composition of Processed Material Obtained by ExemplaryProcedures

Waste material was separated in an aqueous salt solution comprisingabout 10 weight percents NaCl, according to the procedures described inExample 1. The separated low density portion of the waste material wasthen used as a feedstock for processing by mixing and heating accordingto the procedures described in Example 2. A representative sample of theobtained processed material (in its extruded form) is depicted in FIGS.4A and 4B.

For comparison, waste material from the same source was also processedby mixing and heating according to the procedures described in Example2, without a prior separation process.

When using the feedstock produced via separation of waste material,during the heating and mixing, the heated material passed through 3 mmscreens which were intended to block contents which do not melt orsoften. In contrast, when using (non-separated) waste material, thescreens could not be used because they immediately became clogged bysolid, inorganic materials.

Similarly, processed material obtained using the feedstock produced viaseparation of waste material could be readily pelletized, whereas theprocessed (non-separated) waste material clogged the pelletizer.

The density of the processed material obtained using the abovementionedfeedstock was 1.07 grams/cm³, whereas the density of the processed(non-separated) waste material was 1.29 grams/cm³. This result confirmsthat the separation results in a substantial reduction in the density ofthe processed material derived from waste material.

The mineral composition of the samples was then analyzed by extracting10 grams of each sample in 500 ml of boiling water, and performing anelemental analysis on the water by inductively coupled plasma (ICP) massspectroscopy. The concentrations of elements for which at least 1mg/liter was detected (in at least one sample), as well as toxic metals(arsenic, barium, cadmium, cobalt, chromium, mercury, nickel, lead,antimony, selenium), are presented in Table 1.

TABLE 1 Concentration (mg/liter) of elements in extract of processedmaterial derived from waste material, with or without prior separationof waste material (N.D. = not detected; underlining indicates relativelyhigh change in concentration; italics indicate greatest changes inconcentration) With separation Element Without separation (in 10% NaClsolution) Boron  2.0  2.4 Calcium 45.4 25.0 Potassium 48.4 16.7Magnesium  0.8  1.6 Sodium 82.6 462    Sulfur 20.9  9.2 Silicon  4.817.4 Arsenic N.D. N.D. Barium   0.011   0.024 Cadmium N.D. N.D. Cobalt  0.010   0.004 Chromium   0.017   0.012 Mercury N.D. N.D. Nickel  0.15 0.03 Lead  0.02  0.01 Antimony  0.06  0.04 Selenium N.D. N.D.

As shown in Table 1, separating the waste material in an aqueous salt(NaCl) solution resulted in a five-fold increase in the concentration ofsodium in the obtained processed material. This indicates that some saltis incorporated into the sorted material obtained using the saltsolution, thereby affecting the composition of the final product.

As further shown therein, separating the waste material in the aqueoussalt solution resulted in a decrease in the concentrations of commonions such as calcium and potassium (but not magnesium), which mayreflect exchange of cations in the waste material by sodium and/orextraction of water-soluble ions by the aqueous salt solution. The smallincrease in magnesium concentration may be due to a presence ofmagnesium in sea salt.

As further shown therein, separating the waste material in the aqueoussalt solution resulted in a decrease in the concentrations of each ofthe detectable toxic metals, except for barium (possibly due to thepresence of barium in sea water). This indicates that the separationprocess reduces toxicity of processed material.

In order to further characterize the elemental composition of theprocessed material obtained via separation of waste material, elementalanalysis was performed by CHNS (carbon, hydrogen, nitrogen, sulfur)flash combustion analysis (using a Thermo Flash EA-1112 elementalanalyzer) and by X-ray photoelectron spectroscopy (XPS).

According to the CHNS elemental analysis, the weight percentage ofcarbon in the processed material obtained via separation of wastematerial was 69.5±0.3%, the weight percentage of hydrogen in theprocessed material was 10.8±0.1%, the weight percentage of nitrogen inthe processed material was 0.38±0.01%, and the weight percentage ofsulfur in the processed material was less than 0.1%.

The weight percentages of elements according to the XPS elementalanalysis are presented in Table 2 (elemental percentages excludehydrogen and helium, which are not detected by this method).

TABLE 2 Elemental composition of exemplary processed material ElementWeight percentage Atom percentage Carbon 64.93 73.95 Oxygen 25.81 22.07Sodium 1.56 0.93 Magnesium 0.15 0.08 Aluminum 0.61 0.31 Silicon 1.670.81 Phosphorus 0.07 0.03 Sulfur 0.06 0.03 Chlorine 2.40 0.92 Potassium0.04 0.02 Calcium 1.62 0.55 Titanium 0.74 0.21 Iron 0.35 0.09

Taken together, the above elemental analyses indicate that processedmaterial obtained via separation of waste material consists primarily ofcarbon (e.g., at least about 60 weight percents), oxygen (e.g., at leastabout 20 weight percents), hydrogen (e.g., about 10 weight percents) anda small amount of nitrogen (e.g., about 0.4 weight percent), with muchof the balance being sodium and chlorine in approximately equimolaramounts (e.g., each representing about 0.9% of the total amount ofatoms). Carbon, oxygen and hydrogen alone represent over 90 percent ofthe total amount of atoms in the material. The significant amount ofsodium and chlorine is presumably due to the salt in the solution usedfor separating.

The composition was further analyzed using calorimetry. 6.67 mg of theprocessed separated waste material was analyzed from 25 to 300° C. at arate of 10° C. per minute.

As shown in FIG. 6, the processed material obtained via separation ofwaste material was characterized by a phase transition at about 109° C.which was associated with a heat of transition of about 32 joules pergram, and by a phase transition at about 153° C. which was associatedwith a heat of transition of about 20 joules per gram.

These results suggest the presence of polyethylene (associated with themelting point of about 109° C.) and polypropylene (associated with themelting point of about 153° C.), both of which are common in wastematerial, and which have a relatively low specific gravity.

The processed material obtained via separation of waste material wascompared to the processed (non-separated) waste material by Fouriertransform infrared (FTIR) spectroscopy. Polyethylene (20%) was added toeach sample.

As shown in FIG. 7, both samples exhibited similar IR peaks at about2800-3000 cm⁻¹ (associated with carbon-hydrogen bonds), but theprocessed material obtained via separation of waste material exhibits adifferent and less complex spectrum in the “fingerprint region” of about600 to 1800 cm⁻¹, as compared to the processed (non-separated) wastematerial. The correlation of the spectra was 0.97 over the range of600-4000 cm⁻¹, but only 0.77 over the range of 600-2724 cm⁻¹.

In addition, the processed material obtained via separation of wastematerial met European Union REACH regulation standards.

This result indicates that separation of the waste material results in aprocessed material that has a more hydrocarbon-like nature, presumablydue to the removal of materials which are denser than hydrocarbons andsimilar materials.

Example 4 Separation of Waste Material Using 15% Salt Solution

Waste material was separated in an aqueous salt solution comprisingabout 15 weight percents NaCl, according to the procedures described inExamples 1 and 3, to obtain a feedstock. The 15% salt solution resultedin incorporation in the feedstock of a higher percentage of relativelydense organic polymers, typically characterized by a relatively highratio of heteroatoms (e.g., poly(ethylene terephthalate), characterizedby C₁₀H₈O₄ units), in the sorted material.

The feedstock was processed by mixing and heating according to theprocedures described in Examples 2 and 3, to obtain a processed materialwhich was moderately denser and/or richer in heteroatoms (e.g., oxygen)than the processed material obtained using a 10% salt solution, asdescribed in Example 3.

The physical properties of the processed material were analyzed bymeasuring tensile strength, tensile modulus, and notched impact strength(according to ISO 179eA standards), and compared to the correspondingproperties of the common polymers low-density polyethylene (LDPE),high-density polyethylene (HDPE) and polypropylene (PP). The results arepresented in Table 3.

TABLE 3 Physical properties of exemplary processed material,polyethylene and polypropylene Processed material prepared by separatingLow-density High-density waste polyethylene polyethylene Polypropylenematerial (LDPE) (HDPE) (PP) Tensile 12 11 27 35 strength (MPa) Tensile375 150 1100 1650 modulus (MPa) Tensile 85 95 9 9 strength (%) notchedimpact 52.5 60 4 2.5 strength - ISO 179eA (kJ/m²)

The melt-flow index of the processed material was measured according toISO 1133 standards at a temperature of 190° C., and found to be 3.6grams per 10 minutes.

In contrast, the melt flow index of processed material prepared byheating and mixing non-separated waste material could not be measured,as the material did not flow at 190° C.

These results indicate that the separation of waste material forpreparing a feedstock, as described herein, improves the flowability ofthe obtained processed material, and that the physical properties of theobtained processed material are similar to those of polyethylene.

Example 5 Separation of Waste Material Using 20% Salt Solution

Waste material was separated in an aqueous salt solution comprisingabout 20 weight percents NaCl, according to the procedures described inExamples 1 and 3, to obtain a feedstock. The 20% salt solution resultedin incorporation in the feedstock of a higher percentage of relativelydense organic polymers, typically characterized by a relatively highratio of heteroatoms (e.g., poly(ethylene terephthalate), characterizedby C₁₀H₈O₄ units), in the sorted material, as compared to the feedstocksdescribed in Examples 3 and 4.

The feedstock was processed by mixing and heating according to theprocedures described in Examples 2 and 3, to obtain a processed materialwhich was moderately denser and/or richer in heteroatoms (e.g., oxygen)than the processed material obtained using a 10% salt solution, asdescribed in Example 3, or the processed material obtained using a 15%salt solution, as described in Example 4.

Example 6 Processed Material Derived from Waste Material Mixed withPolypropylene Copolymer

Processed material prepared as described in Example 5 was combined withpolypropylene copolymer at a weight ratio of 30:70 (processed material:polypropylene copolymer) to form a plastic material. Five differentbatches of the plastic material were prepared, and their physicalproperties were analyzed by measuring density, tensile strength atyield, tensile modulus, elongation at yield, elongation at break andIzod impact strength (notched and unnotched samples). The results arepresented in Table 4 below.

As shown in Table 4, batch-to-batch variations were relatively small,indicating that the product obtained by the methodology described hereinis reproducible.

In addition, the obtained impact strengths were higher than those ofsimilar plastic materials prepared using processed material prepared byheating and mixing non-separated waste material (data not shown).

TABLE 4 Physical properties of mixtures of exemplary processed materialwith polypropylene copolymer Average ± Batch Batch Batch Batch Batchstandard 1 2 3 4 5 deviation Density (g/cm³) 0.9461 0.9031 0.9281 0.92190.9289 0.9256 ± 0.0155 Tensile strength 19.4 21.1 19.7 20.7 19.4  20.1 ±0.8 at yield (MPa) Tensile modulus 1158 1215 1110 1194 1100   1155 ± 50(MPa) Elongation 5 5 6 5 6   5.4 ± 0.5 at yield (%) Elongation 11 10 1412 13    12 ± 1.6 at break (%) Izod impact 72 65 71 75 75    72 ± 4strength-notched (J/m) Izod impact strength- 475 521 526 525 500   509 ±22 unnotched (J/m)

Example 7 Spectroscopic Analysis of Processed Material Derived fromWaste Material

A feedstock comprising waste material separated in an aqueous saltsolution comprising about 20 weight percents NaCl was processed asdescribed in Example 5. The feedstock was supplemented with polyethyleneprior to processing of the feedstock. The obtained processed materialwas examiner by X-band electron paramagnetic resonance (EPR) and bynuclear magnetic resonance (NMR) spectroscopy.

As shown in FIG. 8, the main feature of the EPR spectrum was ananisotropic signal of a carbon radical, with g1=2.7, g2=2.19 and g3=1.7,giving an isotropic g value of 2.20 (i.e., (2.7+2.19+1.7)/3).

This high g value, as compared to a classical carbon radical which ischaracterized by a g value of about 2.0, suggests an influence of adelocalized free electron surrounding the carbon radicals, thusgenerating a local magnetic field and increased g value.

As the carbon electrons are embedded in a polymeric structure and cannotrotate freely, an anisotropic EPR spectrum was obtained, with differentg1, g2 and g3 values, representing interaction of each of the x, y and zcomponents of the spin vector carbon with the external magnetic field.

In addition, the peak-to-peak width (ΔHpp) observed in the EPR spectrumwas very broad, about 1200 G (gauss), as compared to 1-20 G for atypical free carbon radical, and about 200 G for alkyl or allyl radicalsin cellulose (for which the signal is broadened by hyperfine structuredue to interaction of hydrogen atoms surrounding the carbon radical).The very broad signal suggests that the sample may contain severalspecies of carbon radicals and/or that significant dipolar interactionsbetween neighboring unpaired electrons are present.

The composition of the processed material was further characterized bysolid-state NMR spectroscopy, performed using a Chemagnetics™ Infinityconsole (300 MHz proton frequency) with a Chemagnetics™ triply resonantvariable temperature probe. ¹³C spectra provided information regardingmolecules in the processed material.

As shown in FIG. 9A, the NMR spectrum was dominated by peaks at 28, 31,32.8 and 34 ppm (not shown) that are characteristic of polyethylene (PE)polymer, and which were far stronger than the peaks characteristic ofcellulose. The peak at 32.8 ppm is typical of highly ordered arrangementof the aliphatic polymer chains in polyethylene, also called crystallinePE. The peak at 31 ppm is of semi-crystalline PE where chains are lesstightly packed and some disorder in the polymer exists. Asemi-quantitative analysis of the two peaks shows that about 2:1 existbetween the crystalline and semi-crystalline polymer phases. Peaks at21.8, 23.8, 26.5, 28.1 ppm and at 38.2 and 44 ppm flank the main polymerlines. These lines and their ratios are indicative of the degree ofbranching in high-density polyethylene (HDPE). In typical commercialHDPE, the main polymer chain CH₂ groups appear at 27.1-27.4 and 34-37.5ppm and the branched chain CH₂ carbons at 26.6 ppm and CH₃ carbons at19.9 ppm. Some shifts are possible compared to the these values due tochanges in measurement conditions and in material processing, therefore,the line at 21.8 is identified at branched CH₃, the 26.5 as branched CH₂and main polymer lines at 28.1 and 38.2. The observed peak at 44 ppm wasassociated with C—OH or open chain ether group either in a polymer or ina smaller molecule. It is less than 1% of the total carbon content inthe spectrum.

As shown in FIG. 9B, the NMR spectrum showed peaks at 65.8, 72, 75,83.5, 89 and 105.5 ppm, which were identified as those ofhighly-crystalline cellulose, in accordance with Atalla et al. [J AmerChem Soc 1980, 102:3249]. Peaks typical of lignin were not observed.

The lines at 94.6 and 96.5 ppm and the symmetric lines at −30.8 and−31.9 ppm are sidebands of the main PE carbon line due to samplespinning at 8000 Hz and have no chemical importance, as is the case withthe small line observed at 160.1 ppm.

The weakness of NMR signal associated with lignocellulose as comparedwith polyolefin signal suggests that free radicals present in theprocessed material (as demonstrated by the EPR spectrum) selectivelyreduce the lignocellulose NMR signal, which indicates that free radicalsare concentrated in lignocellulosic material in the processed materialrather than in polyolefins in the processed material.

Example 8 Effect of Hypertonic Solution on Biomass in Waste Material

6 grams of fresh organic waste (carrot, cucumber, banana peels) wasplaced in samples of 60 ml fresh water or 60 ml of salt water with about20 weight percents, and incubated at room temperature for 3 hours.Filtrates of each sample were then analyzed by ¹³C-NMR spectroscopy,performed as described in Example 7.

As shown in FIGS. 10A and 10B, the filtrate from the salt solutionexhibited NMR signals in a range of from 60-100 ppm (FIG. 10A), typicalof carbohydrates such as glucose and xylose, whereas no such signalswere observed for the filtrate obtained from fresh water.

These results indicate that the use of hypertonic solutions to separatewaste material breaks cell walls and facilitates release ofcarbohydrates.

Example 9 System for Separating Waste Materials According to SpecificGravity

An exemplary system for separating waste materials according to specificgravity according to some embodiments of the invention is shown in FIG.11. The system is may optionally be incorporated within a larger systemfor sorting and/or processing waste material, as described herein.

The system comprises a container 300 which is at least partially filledwith liquid 310, and optionally a stirrer 350 (e.g., a paddle wheel)within container 300 or in communication with container 300. Liquid 310is selected to have a specific gravity suitable for separating wastematerial (e.g., in a range of from 1.00 to 2.50). Liquid 310 isoptionally an aqueous solution. Container 300, along with its associateddevices (as described herein), is also referred to as a “separator”.

Container 300 is configured to allow waste material (optionally shreddedwaste material) to enter (as indicated by arrow 320), and to allow somewaste material at surface 315 of the liquid 310, and optionallyadditional material in liquid 310 which does not sediment (e.g., is notat the bottom of container 300), to exit container 300 via outlet 330(as indicated by arrow 325).

Optional conveyor 365 is located at or near surface 315, and isconfigured to convey material at or near surface 315 of the liquid 310out of container 300 via outlet 330. For example, material floating atsurface 315 comes into contact with conveyor 365, allowing conveyor 365to convey the material.

Optional conveyor 360 is configured to convey material at or near bottomof container 300 (e.g., sediment) out of container 300. Conveyor 360 mayoptionally be configured to raise material above surface 315 beforeexiting container 300.

Conveyor 365 and/or conveyor 360 optionally comprise teeth and/orgrooves and/or the like (not depicted), configured for grabbingmaterial, so as to facilitate conveying.

Outlet 330 is optionally configured to remove, optionally by gravityand/or centrifugal force, at least some liquid 310 which adheres toand/or is absorbed by sorted materials exiting via outlet 330, orotherwise leaks from container 300 into outlet 330. Liquid 310 which isremoved in outlet 330 may optionally be returned to container 300 viaoptional conduit 340.

Liquid 310 is optionally a solution (optionally a salt solution) or asuspension, comprising a solvent (optionally water) and an additionalsubstance (e.g., a solute and/or a suspended substance).

The system is optionally configured to adjust a specific gravity of saidliquid to a predetermined value (e.g., a value within a predeterminedrange).

Optional reservoir(s) 380 comprises water and/or additional substance,which enter container 300 via conduit(s) 390 to replenish and/or adjusta composition and/or specific gravity of liquid 310.

Optional monitor 370 is in communication with container 300, andmonitors a composition and/or specific gravity of liquid 310. Monitor370 is optionally configured to control entry of water and/or additionalsubstance from reservoir(s) 380 into container 300, so as to control acomposition and/or specific gravity of liquid 310.

Optional container 395 receives sorted material exiting container 300via outlet 330 (as indicated by arrow 325), and is filled with a liquid(not shown) adapted for rinsing off at least some liquid 310 whichadheres to and/or is absorbed by sorted materials exiting via outlet330.

In some embodiments, conveyor 315 extends into outlet 330, andoptionally into container 395.

In some embodiments, an additional conveyor (not shown) conveys materialthrough outlet 330 and/or container 395.

Outlet 330 and/or container 395 is optionally configured for conveyingsorted material to an apparatus for shredding the sorted material (e.g.,shredding to a finer particle size) and/or to an apparatus for heatingand mixing a feedstock derived from waste material as described herein.

Container 300 and/or container 395 is optionally in communication with afiltration apparatus (not shown), optionally a reverse osmosisfiltration apparatus, adapted for filtering out solutes and/or smallparticles of material. In some embodiments, a filtration apparatus incommunication with container 395 is adapted for filtering residualsolute of liquid 310 out of the liquid in container 395. In someembodiments, a filtration apparatus in communication with container 300is adapted for filtering small particles of material out of liquid 310in container 300.

In some embodiments, a system comprises a plurality (e.g., a pair) ofcontainers 300 (e.g., a plurality of separators), configured foroperating in parallel and/or in tandem, each configured as describedherein (e.g., with conveyors 360 and 365, stirrer 350 and outlet 330),being in communication with a single container 395. Such a configurationmay allow for continuous operation of the system when one container 300is not available for separating waste materials (e.g., due tomaintenance and/or removal of waste materials therefrom) and/or forperforming multiple cycles of separation (e.g., using liquids withdifferent specific gravities).

Example 10 System for Separating and Processing Waste Materials

An exemplary system for separating waste materials according to specificgravity and processing the waste materials according to some embodimentsof the invention is shown in FIG. 12. The system may optionally beincorporated within a larger system for processing waste material, asdescribed herein.

The system optionally comprises a waste reservoir 400 which is adaptedfor storing (e.g., for up to 24 hours or more) a large amount (e.g.,about 25 tons) of waste materials without polluting (e.g., by odorpollution and/or leakage of liquids) the surrounding environment and/orfor receiving transported waste materials (e.g., from a waste disposalvehicle). Optional waste reservoir 400 is configured for conveying wastematerial to a first separator 410 via optional conduit 402, andoptionally further configured for conveying gas released by the wastematerial therein to optional gas control system 496 via optional conduit404 (e.g., a conveyor belt in communication with a bottom of reservoir400). Waste reservoir 400 is optionally configured for monitoring aweight of waste material therein.

Optional conduit 402 (e.g., a conveyor belt) is configured for conveyingmaterial comprising liquids without leakage (e.g., without leakagebetween slats of a conveyor belt). Conduit 402 is optionally configuredfor conveying waste material at a rate of at least 0.5-3 tons per hour.

First separator 410 contains an aqueous salt solution (e.g., at a volumeof about 3-4 m³) and is configured for separating waste materialsaccording to specific gravity as described herein (e.g., configured as asystem described in Example 9), and for conveying partially sortedmaterials obtained by separation to first shredder 420 via conduit 412.First separator 410 is optionally further configured for separating oilswhich float on a surface of the aqueous salt solution (e.g., byskimming) from the partially sorted materials and aqueous salt solution,first separator 410 optionally comprising a skimmer adapted for skimmingoils (e.g., a weir skimmer, oleophilic skimmer and/or metallic skimmerdescribed herein).

First separator 410 is adapted for partial separation (e.g., bycompression and/or drainage) of liquid (composed to a large degree ofthe aqueous salt solution) from partially sorted material exiting theseparator and maintaining the separated solution in the separator. Theseparated liquids may further include oils originating in the wastematerial. First separator 410 is in communication with separatorsolution control system 494 via conduit(s) 416. First separator 410,separator solution control system 494 and conduit(s) 416 are configuredfor conveying liquid (composed to a large degree of the aqueous saltsolution) from separator 410 to separator solution control system 494for monitoring the content (e.g., specific gravity) of the solutionand/or for conveying aqueous salt solution or any ingredients thereoffrom separator solution control system 494 to separator 410, forreplenishing or otherwise controlling the solution in separator 410.First separator 410 is optionally further configured for conveyingseparated materials such as inorganic materials to optional inorganicmaterial bin 492 via optional conduit 414.

First shredder 420 is configured for shredding (e.g., by cutting blades)partially sorted material received from separator 410 into crudelyshredded pieces of about 12 mm in size, and for conveying the shreddedpartially sorted material to second separator 430 via conduit 422.Shredder 420 is optionally further configured for conveying liquid fromthe shredded partially sorted material (e.g., by compressing and/ordraining the shredded partially sorted material) via optional conduit424 to optional liquid control system 490. The liquid may include oilsoriginating in the waste material.

Second separator 430 contains an aqueous salt solution (e.g., at avolume of about 3-4 m³) and is configured for separating crudelyshredded partially sorted materials received from shredder 420 accordingto specific gravity as described herein (e.g., configured as a systemdescribed in Example 9), and for conveying sorted materials afterseparation to second shredder 440 via conduit 432. Second separator 430is optionally further configured for separating oils which float on asurface of the aqueous salt solution (e.g., by skimming) from thepartially sorted materials and aqueous salt solution, second separator430 optionally comprising a skimmer adapted for skimming oils (e.g., aweir skimmer, oleophilic skimmer and/or metallic skimmer describedherein).

Second separator 430 is adapted for partial separation (e.g., bycompression and/or drainage) of liquid (composed to a large degree ofthe aqueous salt solution) from sorted material exiting the separatorand maintaining the separated solution in the separator. The separatedliquids may further include oils originating in the waste material.Second separator 430 is in communication with separator solution controlsystem 494 via conduit(s) 436. Second separator 430, separator solutioncontrol system 494 and conduit(s) 436 are configured for conveyingliquid (composed to a large degree of the aqueous salt solution) fromseparator 430 to separator solution control system 494 for monitoringthe content (e.g., specific gravity) of the solution and/or forconveying aqueous salt solution or any ingredients thereof fromseparator solution control system 494 to separator 430, for replenishingor otherwise controlling the solution in separator 430. Second separator430 is optionally further configured for conveying separated materialssuch as inorganic materials to optional inorganic material bin 492 viaoptional conduit 434.

Second shredder 440 is configured for further shredding (e.g., bycutting blades) sorted material received from separator 430 intoshredded pieces of about 5-6 mm in size, and for conveying the shreddedsorted material to optional mixer 460 via conduit 442 (e.g., a conveyorbelt). Shredder 440 is optionally further configured for conveyingliquid from the shredded sorted material (e.g., by compressing and/ordraining the shredded sorted material) via optional conduit 444 tooptional liquid control system 490. The liquid may include oilsoriginating in the waste material.

Any one or more of first separator 410, first shredder 420, secondseparator 430 and second shredder 440 optionally comprises a screw pressconfigured for compressing partially sorted material exiting theseparator and/or shredder, to thereby separate a portion of the liquidsfrom partially sorted material. Optionally, first shredder 420 and/orsecond shredder 440 comprise a screw press.

Optional additional material reservoir 450 (e.g., a silo) is configuredfor conveying an additional material to be added to the sorted material(e.g., an additional material described herein) to mixer 460 viaoptional conduit 452. Reservoir 450 may optionally be configured forbreaking any lumps in the additional material. Conduit 452 maycommunicate with mixer 460 separately from conduit 442, or conduits 452and 442 may be joined to form a single conduit in communication withmixer 460. Conduit 452 is optionally configured for conveying theadditional material to an optional separator (not shown) for sorting theadditional material, after which the sorted additional is conveyed tomixer 460.

Mixer 460 is configured for mixing sorted material received via conduit442 and optionally additional material received via conduit 452, forforming a feedstock. Mixer 460 is optionally configured for mixing thesorted material in an acidic solution (e.g., aqueous hydrochloric acid,pH 2). The acidic solution is optionally sufficiently acidic so as toresult in cleavage of lignocellulose in the sorted material to smallerunits (e.g., cleavage of polysaccharide to smaller saccharide units).Mixer 460 is optionally further configured for conveying liquid releasedfrom the sorted material to optional liquid control system 490 viaoptional conduit(s) 464.

Optionally, mixer 460 is a component (e.g., the mixer component) ofmixer/reactor 480, and optional buffer container 470 and optionalconduits 462 and 472 are not present.

Alternatively, mixer 460 is configured for conveying the feedstockdirectly or indirectly to mixer/reactor 480 via optional conduit 462.Conduit 462 is optionally in direct communication with mixer/reactor480.

Alternatively, conduit 462 is in communication with optional buffercontainer 470, which is configured (e.g., in a form of a hopper) forconveying feedstock to mixer/reactor 480 via conduit 472 at a controlledrate which is adapted for operation of mixer/reactor 480. The controlledrate may be different than the rate at which the feedstock is conveyedto container 470 via conduit 462. Buffer container 470 is optionallyfurther configured for conveying gas released from the feedstock tooptional gas control system 496 via optional conduit 476, and/or forconveying liquid released from the feedstock to optional liquid controlsystem 490 via optional conduit 474.

Mixer/reactor 480 is configured for subjecting the feedstock to shearforces and heating as described herein (e.g., configured as described inFIG. 4), and for releasing gas from heated feedstock (e.g., viavent(s)). Mixer/reactor 480 is optionally configured for extruding aprocessed material.

Mixer/reactor 480 optionally comprises a first zone and second zone formixing and heating. The first zone is configured for receiving feedstockfrom conduit 472, subjecting the feedstock to mixing and heating at afirst temperature (e.g., at about 110° C.) sufficient for forming arelatively homogeneous mixture (e.g., kneading), and releasing gas. Thesecond zone is configured for receiving material from the first zone,subjecting the material to mixing with shear forces as described hereinand heating at a second temperature (e.g., at about 180-225° C.), andreleasing gas, and optionally for extruding a processed material. Thesecond zone is optionally configured as an extruder (e.g., as describedherein).

Mixer/reactor 480 optionally comprises at least one mixer adapted forsubjecting incoming material to intensive shearing forces, for example,by rotation of intersecting spiral-shaped blades (e.g., as in a Banbury®mixer). Such a mixer may be configured as a first zone of mixer/reactor480 (as described herein) and/or for receiving material from conduit 472and conveying material to a first zone of mixer/reactor 480 (asdescribed herein).

Mixer/reactor 480 is optionally in communication with a pelletizer (notshown) configured for preparing pellets from processed material conveyed(e.g., by extrusion) from mixer/reactor 480.

Optionally, gas is conveyed via optional conduit(s) 484 to optional gascontrol system 496. Optionally, conduit(s) 484 comprises at least oneconduit in communication with a first zone described herein and/or atleast one conduit in communication with a second zone described herein.

Separator solution control system 494 is configured for cleaning one ormore separator solutions (e.g., by removal of particles of wastematerial by filtration, removal of oils by any suitable oil-waterseparation technique, and/or removal of foam, which may be caused, forexample, by detergents in waste material), and for controlling an amountof solution in separator 410 and/or 430. Solution control system 494 isoptionally configured to receive information from one or more monitors(not shown) which detect an amount of solution in separator 410 and/or430. Solution control system 494 optionally comprises a plurality (e.g.,two) of parallel mechanisms for cleaning solutions, such that the systemcan remain operative during maintenance of one mechanism (e.g., cleaningand/or replacing a filter and/or oil-water separator).

Solution control system 494 is optionally in communication with areservoir for collecting oils removed by solution control system 494.Alternatively or additionally, the reservoir for collecting oils is incommunication with first separator 410 and/or second separator 430, andis for collecting oils separated (e.g., by skimming) in first separator410 and/or second separator 430, as described herein.

Optional gas control system 496 is optionally configured for condensing(e.g., forming water from steam) and/or storing at least a portion ofgas received from reservoir 400, container 470 and/or mixer/reactor 480,and optionally further configured for separating liquids (e.g., water)formed by the condensation. Such a gas (e.g., methane) may have anindustrial use (e.g., as a fuel). Optional gas control system 496 isoptionally configured to reduce pollution (e.g., air pollution, waterpollution and/or soil pollution) by gas received from reservoir 400,container 470 and/or mixer/reactor 480, and/or by liquids (e.g., water)formed by the condensation.

Optional liquid control system 490 is configured for collecting andoptionally treating a liquid received from reservoir 400, shredder(s)420 and/or 440, mixer 460 and/or container 470. Such a compound may havean industrial use (e.g., use in feedstock). Liquid control system 490 isoptionally further configured for conveying a compound (e.g.,carbohydrate) from a liquid to mixer 460 via conduit 464.

Treating the liquid may optionally comprise concentrating a compound(e.g., carbohydrate) in the liquid (e.g., by filtration and orevaporation of the liquid), fermenting and/or processing thecarbohydrate(s) by fermentation, heating, and/or reaction with a reagent(e.g., as described herein).

The salt in the aqueous salt solutions of separator 410 and/or 430optionally consists essentially of sea salt (e.g., NaCl with someadditional salts present). The salt solution is optionally sea water orconcentrated sea water or diluted sea water.

Materials comprised by the system are selected to be suitable foroperation in a corrosive environment while minimizing galvaniccorrosion.

Although the invention has been described in conjunction with specificembodiments thereof, it is evident that many alternatives, modificationsand variations will be apparent to those skilled in the art.Accordingly, it is intended to embrace all such alternatives,modifications and variations that fall within the spirit and broad scopeof the appended claims.

All publications, patents and patent applications mentioned in thisspecification are herein incorporated in their entirety by referenceinto the specification, to the same extent as if each individualpublication, patent or patent application was specifically andindividually indicated to be incorporated herein by reference. Inaddition, citation or identification of any reference in thisapplication shall not be construed as an admission that such referenceis available as prior art to the present invention. To the extent thatsection headings are used, they should not be construed as necessarilylimiting.

1. A method of processing waste material so as to form a non-particulateprocessed material, the method comprising: removing at least a portionof inorganic materials in the waste material, to thereby obtain a sortedmaterial containing at least 90 weight percents of an organic material;providing a feedstock having a water content of at least 15 weightpercents, wherein at least 50 weight percents of the dry weight of saidfeedstock is said sorted material; subjecting said feedstock to mixingvia shear forces; and subjecting said feedstock to heating, wherein:said removing comprises separating materials according to specificgravity, said separating comprising contacting the waste material with aliquid selected such that said at least a portion of inorganic materialssink; and the feedstock is subjected to said mixing and said heatingwithout being dried, thereby obtaining a non-particulate processedmaterial.
 2. The method of claim 1, wherein at least 90 weight percentsof the dry weight of said feedstock is said sorted material.
 3. Themethod of claim 1, wherein less than 10% of a volume of saidnon-particulate processed material consists of particles having a volumeof at least 0.2 mm³.
 4. The method of claim 1, wherein said separatingmaterials according to specific gravity comprises obtaining a sortedmaterial containing at least 90 weight percents of material having aspecific gravity within a pre-selected range.
 5. (canceled)
 6. Themethod of claim 1, wherein said separating materials according tospecific gravity further comprises removing at least a portion of apolymer selected from the group consisting of a thermoset polymer and asynthetic polymer having a melting point of at least 250° C. in thewaste material, to thereby obtain a sorted material containing at least90 weight percents of an organic material other than said thermosetpolymer and said synthetic polymer having a melting point of at least250° C.
 7. The method of claim 1, wherein said water content of saidfeedstock is at least 40 weight percents.
 8. The method of claim 1,wherein at least 70 weight percents of the dry weight of said feedstockis lignocellulose.
 9. The method of claim 1, wherein no more than 5weight percents of the dry weight of said feedstock is inorganicmaterial.
 10. The method of claim 1, wherein from 15 to 30 weightpercents of the dry weight of said feedstock is synthetic polymers. 11.The method of claim 1, wherein at least 1 weight of the dry weight ofsaid feedstock is inorganic salts.
 12. The method of claim 1, furthercomprising contacting the waste material or sorted material with anacidic substance, to thereby provide said feedstock.
 13. (canceled) 14.A method of sorting waste material, the method comprising: separatingmaterials in the waste material according to specific gravity, the wastematerial being substantially unsorted municipal solid waste, saidseparating comprising contacting the waste material with an aqueousliquid selected such that a portion of said waste material sinks, tothereby obtain a sorted material containing at least 90 weight percentsof material having a specific gravity within a pre-selected range. 15.The method of claim 14, wherein said pre-selected range is no more than1.25.
 16. The method of claim 1, further comprising shredding the sortedmaterial subsequent to said contacting the waste material with saidliquid.
 17. The method of claim 14, wherein a specific gravity of saidliquid is at least 1.05.
 18. The method of claim 14, wherein said liquidcomprises an aqueous salt solution.
 19. The method of claim 14,comprising said contacting the waste material with an aqueous liquid, tothereby obtain a partially sorted material, and further comprisingsubjecting said partially sorted material to at least one additionalcycle of separating materials according to specific gravity, saidseparating comprising contacting the partially sorted material with anadditional liquid, to thereby obtain said sorted material.
 20. Themethod of claim 14, further comprising separating at least a portion ofoils from said sorted material.
 21. A polymeric material obtainable bythe method of claim
 1. 22. The polymeric material of claim 21, being athermoplastic polymeric material.
 23. The polymeric material of claim21, being characterized by a density below 1.2 gram/cm³.
 24. Thepolymeric material of claim 21, wherein a concentration of carbon in thematerial is at least 55 weight percents.
 25. The polymeric material ofclaim 21, wherein a concentration of oxygen in the material is at least20 weight percents.
 26. The polymeric material of claim 21, wherein atotal concentration of carbon and oxygen in the material is at least 80weight percents and/or at least 95 percent of the non-hydrogen atoms inthe material are carbon or oxygen atoms.
 27. The polymeric material ofclaim 21, wherein a total concentration of carbon, hydrogen and oxygenin the material is at least 90 weight percents.
 28. The polymericmaterial of claim 21, wherein a total concentration of carbon, hydrogen,oxygen, nitrogen, alkali metal and halogen atoms in the material is atleast 93 weight percents.
 29. (canceled)
 30. The polymeric material ofclaim 21, wherein at least 97 percent of the non-hydrogen atoms in thematerial are carbon, oxygen, nitrogen, alkali metal or halogen atoms.31. The polymeric material of claim 21, wherein a molar concentration ofalkali metals in the polymeric material is at least 50% higher than amolar concentration of alkali metals in the dry weight of said wastematerial.
 32. The polymeric material of claim 21, wherein a molarconcentration of halogens in the polymeric material is at least 50%higher than a molar concentration of halogens in the dry weight of saidwaste material.
 33. The polymeric material of claim 21, wherein amelt-flow index of the polymeric material is at least 1 gram per 10minutes at a temperature of 190° C.
 34. An article-of-manufacturingformed from the polymeric material of claim
 21. 35. Anarticle-of-manufacturing comprising two or more materials adhered toand/or blended with one another, wherein at least one of said materialsis the polymeric material of claim
 21. 36. (canceled)
 37. A system forprocessing a waste material to form a non-particulate processedmaterial, the system comprising: a separator configured for removing atleast a portion of inorganic materials from the waste material byseparating materials in the waste material according to specificgravity, the separator containing a liquid selected such that at least aportion of inorganic materials sink, to thereby provide a sortedmaterial containing at least 90 weight percents of an organic material;an apparatus for subjecting a feedstock to mixing via shear forces, saidapparatus comprising a first mixing zone and a second mixing zone, eachindependently being adapted for subjecting the waste material toheating; and a first vent and a second vent, each being adapted forremoving gases released during said mixing and said heating from saidapparatus, the system being configured for providing to said apparatus afeedstock comprising said sorted material, and having a water content ofat least 15 weight percents, and the apparatus being configured forsubjecting said feedstock to mixing in said first mixing zone andremoving said gases from said first vent, and subsequently subjectingsaid feedstock to mixing in said second mixing zone and removing saidgases from said second vent, to thereby obtain a processed material,wherein the feedstock is subjected to said mixing and said heatingwithout being dried. 38-39. (canceled)
 40. The system of claim 37, beingconfigured for removing at least a portion of a polymer selected fromthe group consisting of a thermoset polymer and a synthetic polymerhaving a melting point of at least 250° C. from the waste material, tothereby obtain a sorted material containing at least 90 weight percentsof an organic material other than said thermoset polymer and saidsynthetic polymer having a melting point of at least 250° C.
 41. Thesystem of claim 37, wherein said water content of said feedstock is atleast 40 weight percents.
 42. The system of claim 37, wherein said firstmixing zone and said second mixing zone are each independently adaptedfor heating said feedstock at a temperature in a range of from 90° C. to230° C.
 43. The system of claim 37, wherein said apparatus comprises ascrew for effecting said mixing.
 44. A system for sorting a wastematerial which is substantially unsorted municipal solid waste, thesystem comprising: a separator configured for separating materials inthe waste material according to specific gravity, the separatorcontaining a liquid selected such that a portion of said waste materialsinks, to thereby obtain a sorted material containing at least 90 weightpercents of material having a specific gravity within a pre-selectedrange. 45-46. (canceled)
 47. The system of claim 44, wherein a specificgravity of said liquid is at least 1.05.
 48. The system of claim 44,wherein said liquid comprises an aqueous salt solution.
 49. The systemof claim 44, comprising a first separator configured for separatingmaterials according to specific gravity to thereby obtain a partiallysorted material, and at least one additional separator configured forsubjecting said partially sorted material to at least one additionalcycle of separating materials according to specific gravity, saidadditional separator containing an additional liquid selected such thata portion of said partially sorted material sinks.
 50. The system ofclaim 44, further comprising at least one apparatus configured forseparating oils from said liquid.